Information-recording apparatus, information-recording method, program storage medium and program

ABSTRACT

An information-recording apparatus is disclosed wherein an area to be allocated to a new FS can be set when an area allocated to FSes has been all consumed. The information-recording apparatus includes a track division means. When a track set on a recording medium as a track allocated to FSes no longer has a free area, on the basis of a command, the track division means divides a track allocated on the recording medium in advance to files into an area to be used as a track allocated to FSes and an area to be used as a track allocated to files.

CROSS REFERENCES TO RELATED APPLICATIONS

The present invention contains subject matter related to Japanese PatentApplication JP 2004-317846 filed in the Japanese Patent Office on Nov.1, 2004, the entire contents of which being incorporated herein byreference.

BACKGROUND OF THE INVENTION

The present invention relates to information-recording apparatus, aninformation-recording method adopted in the apparatus, a programimplementing the method and a program storage medium used for storingthe program. More particularly, the present invention relates toinformation-recording apparatus, in which an area for recording an FS(File System) can be allocated in a recording medium if necessary as aportion of an area used for recording files even when the FS is updatedfrequently and/or information is added to the FS frequently, if the FSis stored in scattered areas, pieces of information stored in thescattered areas can be collected into a single area by carrying out anoptimization process so that information can be read out and writtenfrom and into the recording medium at a high speed, the amount ofconsumption of a TDMA (Temporary Defect Management Area) can be reducedand, if it is known from the beginning that logical write operations areto be carried out frequently, the recording medium is formatted to setthe TDMA at a sufficiently large size so that the TDMA can be updatedfrequently, as well as relates to an information-recording methodadopted in the apparatus, a program implementing the method and aprogram storage medium used for storing the program.

A technology for recording files into a recording medium with a largestorage capacity has been becoming popular.

In addition, a variety of formats of recording files into such arecording medium with a large storage capacity has also been proposed.

A typical one of the formats is a UDF (Universal Disc Format) used in aDVD (Digital Versatile Disc). For more information, refer to documentssuch as Non-patent Document 1: Universal Disk Format SpecificationRevision 2.50 Apr. 30, 2003 Optical Storage Technology Association.

By the way, in UDF specifications of Ver. 2.50, file-system informationis collected and placed in a single area referred to as a metadatapartition and includes an additional function located at a logicaladdress in the metadata partition.

In the case of a write-once recording medium, which is a recordingmedium allowing data to be stored thereon only once, in an operation toupdate a file stored thereon or the file system recorded thereon, theupdated file or the updated file system must be recorded in a new areaof the recording medium. It is thus necessary to update the logicaladdress of the file or the file system to a new logical addresscorresponding to the physical address of the new area.

In the case of a Blu-ray Disc conforming to the UDF specifications ofVer. 2.50, a file and/or file-system information are recorded on thedisc as shown in the upper diagram of FIG. 1. In the followingdescription, the Blu-ray Disc is referred to as a BD. FIG. 1 is diagramseach showing a typical recording state of the BD, which serves as awrite-once recording medium. In the following description, the BDserving as a write-once recording medium is referred to as a BD-R(Blu-ray Disc-Recordable). In the figure, LSNs (Logical Sector Numbers)or logical addresses are set, starting from the left side of the figure.In the upper diagram of FIG. 1, LSNs of 0 to N are assigned to an areaset as a volume space. An area pointed to by the first LSN of 0 as anarea marked with the word ‘Reserved’ is a reserved area. Following thereserved area, an area marked with a character string of ‘VRS’ (VolumeRecognition Sequence) is an area used for recording informationindicating the type of the file system. Following the area marked with acharacter string of ‘VRS’, an area marked with the phrase ‘Files(Stream+DB)’ is an area used for recording stream data written by anapplication program onto the BD in a recording process or stream data tobe read out by an application program from the BD in a reproductionprocess and used for recording database information to be used in therecording or reproduction process. Following the area marked with thephrase ‘Files (Stream+DB)’, an area marked with the phrase ‘Files (notunder BD management)’ is an area used for recording data recorded by aprogram other than an application program for recording stream data ontothe BD and reading out stream data from the BD. Following the areamarked with the phrase ‘Files (not under BD management)’, an area markedwith the phrase ‘FS (Metadata)’ is an area used for recordingfile-system information as metadata. Following the area marked with thephrase ‘FS (Metadata)’, two areas each marked with the word ‘Anchor’ areeach an area used for recording anchor information. Sandwiched by thetwo areas each marked with the word ‘Anchor’, an area marked with thephrase ‘Volume Str. (Volume Structure)’ is an area used for recordinginformation on the structure of the volume. It is to be noted that thearea marked with the phrase ‘Files (Stream+DB)’ is a block B0. On theother hand, the area marked with the phrase ‘FS (Metadata)’, the twoareas each marked with the word ‘Anchor’ and the area marked with thephrase ‘Volume Str.’ form a single block B1.

Let us assume for example that stream data is added to the BD-R with arecording state shown in the upper diagram of FIG. 1 and the databaseinformation of the stream data is updated accordingly. In this case,information is recorded onto the BD-R as shown in the lower diagram ofFIG. 1.

That is to say, new stream data added to information recorded in theblock B0 and the database information used for reproduction of theupdated stream data are recorded in a block B0′ following the block B1.In addition, since the updated stream data is recorded in the block B0′,updated file-system information, which is referred to hereafter as anFS, anchor information corresponding to the FS and information on thestructure of the volume are recorded in a block B2. At the same time,the FS information, the anchor information corresponding to the FS andthe information on the structure of the volume, which exist in the blockB1, are put in a state of being unreadable.

SUMMARY OF THE INVENTION

By the way, in the case of a write-once recording medium, which is arecording medium allowing data to be stored thereon only once, in anoperation to update a file stored thereon or the file-system information(which is referred to as an FS) recorded thereon, the updated file orthe updated file-system information must be recorded in a new area ofthe recording medium as described above. It is thus necessary to updatethe logical address of the file or the file-system information to a newlogical address corresponding to the physical address of the new area.

In order to solve the problem of the necessity to update the logicaladdress of the file or the file-system information to a new logicaladdress corresponding to the physical address of the new area, there hasbeen proposed a technique to update file-system information (FS) withoutthe need to update the logical address. In accordance with this proposedtechnique, the updated file-system information is recorded as areplacement of the pre-updating file-system information into either ofan alternate area and a user area, which are allocated in conformitywith file format specifications such as the UDF specifications.

If the process to add or update a file is carried out repeatedly,however, the logical operation carried out on the FS must also berepeated as well. In this case, the amount of management informationused for managing alternate areas used for recording replacements ofpre-updating file-system information inevitably increases. Thus, whenthe process to add or update a file is carried out repeatedly, as aresult, it is feared that the area allocated as the alternate area ismuch consumed. In particular, a TDMA (Temporary Defect Management Area)is much used for storing management information.

In addition, if the FS is updated repeatedly, a track allocated as anarea used for recording FSes can no longer be used for recording an FS.In this case, it is necessary to record the FS in another new area.Since a command for allocating existing tracks is not available,however, it is impossible to set an unused area among areas used forrecording files as an area to be used for recording a new FS. As aresult, there is raised a problem that a new file cannot be recorded oran already existing file cannot be updated.

On top of that, even if an area to be used for recording a new FS can beset, it is feared that the FS is stored in scattered areas and, inaddition, it takes time to read out a file from the disk or write a fileonto the disk because the number of partial areas each to be replacedwith an alternate area increases.

In order to solve the problems described above, inventors of the presentinvention have particularly devised information-recording apparatus, inwhich an area for recording an FS can be allocated in a recording mediumif necessary as a portion of an area used for recording files even whenthe FS is updated frequently and/or information is added to the FSfrequently, if the FS is stored in scattered areas, pieces ofinformation stored in the scattered areas can be collected in a singlearea by carrying out an optimization process so that information can beread out from and written into the recording medium at a high speed, theamount of consumption of a TDMA (Temporary Defect Management Area) canbe reduced and, if it is known from the beginning that logical writeoperations are to be carried out frequently, the recording medium isformatted to set the TDMA at a sufficiently large size so that the TDMAcan be updated frequently, as well as devised an information-recordingmethod adopted in the apparatus.

An information-recording apparatus according to an embodiment of thepresent invention includes track division means, wherein when a trackset on a recording medium as a track allocated to FSes no longer has afree area, on the basis of a command, the track division means divides atrack allocated on the recording medium in advance to files into an areato be used as a track allocated to FSes and an area to be used as atrack allocated to files.

The command has a parameter for specifying an original track to bedivided and one or more parameters for specifying sizes or locations ofresulting areas obtained as a result of division of the original track.The track division means is capable of dividing the original track intothe resulting areas, which start from the beginning of the originaltrack and are defined by the sizes or the locations, and a remainingarea, and setting free portions of the resulting areas and the remainingarea as a track allocated to FSes and a track allocated to files.

The command has a parameter for specifying an original track to bedivided and one or more parameters for specifying sizes or locations ofresulting areas obtained as a result of division of the original track.

The track division means is capable of dividing the original track intoan already recorded area starting from the beginning of the originaltrack, free areas, which follow the already recorded area and aredefined by the sizes or the locations, and a remaining area, and settingthe free areas and the remaining area as a track allocated to FSes and atrack allocated to files.

When a track set on a recording medium as a track allocated to main FSesor mirror FSes no longer has a free area, on the basis of a command, thetrack division means is capable of dividing a track allocated on therecording medium in advance to files into an area to be used as a trackallocated to main FSes or mirror FSes and an area to be used as a trackallocated to files.

An information-recording method according to an embodiment of thepresent invention includes a track division step at which, when a trackset on a recording medium as a track allocated to FSes no longer has afree area, on the basis of a command, a track allocated on the recordingmedium in advance to files is divided into an area to be used as a trackallocated to FSes and an area to be used as a track allocated to files.

According to an embodiment of the present invention, there is provided aprogram storage medium as a medium used for storing a program that canbe read out by a computer for execution wherein the program includes atrack division control step at which, when a track set on a recordingmedium as a track allocated to FSes no longer has a free area, on thebasis of a command, control is executed to divide a track allocated onthe recording medium in advance to files into an area to be used as atrack allocated to FSes and an area to be used as a track allocated tofiles.

According to an embodiment of the present invention, there is provided aprogram as a program to be executed by a computer to carry outprocessing, wherein the processing includes a track division controlstep at which, when a track set on a recording medium as a trackallocated to FSes no longer has a free area, on the basis of a command,control is executed to divide a track allocated on the recording mediumin advance to files into an area to be used as a track allocated to FSesand an area to be used as a track allocated to files.

An information-recording apparatus according to an embodiment of thepresent invention includes track division means, wherein when a trackset on a recording medium as a track allocated to FSes no longer has afree area, on the basis of a command, the area division means divides atrack allocated on the recording medium in advance to files into an areato be used as a track allocated to FSes and an area to be used as atrack allocated to files.

The information-recording apparatus according to an embodiment of thepresent invention can be an independent apparatus or a block forcarrying out an information-recording process.

In accordance with the present invention, the consumption of the TDMAcan be reduced and information can be read out from the recording mediumor written into the recording medium at a higher speed.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects and features of the present invention willbecome clear from the following description of the preferred embodimentsgiven with reference to the accompanying diagrams, in which:

FIG. 1 is an explanatory diagram showing the conventional processing toupdate file-system information;

FIG. 2 is a diagram showing the configuration of an embodimentimplementing a recording/reproduction apparatus to which the presentinvention is applied;

FIG. 3 is a diagram showing the configuration of an embodimentimplementing a recording/reproduction mechanism section employed in therecording/reproduction apparatus shown in FIG. 2;

FIG. 4 is a diagram showing an example of group management;

FIG. 5 is a diagram showing the structure of directories generated bythe typical group management shown in FIG. 4 as well as filesaccommodated in the directories and also generated by the groupmanagement;

FIG. 6 is a diagram showing another example of group management;

FIG. 7 is a diagram showing the structure of directories generated bythe typical group management shown in FIG. 6 as well as filesaccommodated in the directories and also generated by the groupmanagement;

FIG. 8 is an explanatory diagram showing a procedure for making anaccess to a file conforming to a UDF;

FIG. 9 is an explanatory diagram showing a procedure for making anaccess to a file conforming to the UDF;

FIG. 10 is an explanatory diagram showing a technique of relocatingfile-system information at a virtual address;

FIG. 11 is an explanatory diagram showing a technique of relocatingfile-system information at a virtual address;

FIG. 12 is an explanatory diagram showing a technique of relocatingfile-system information at a virtual address;

FIG. 13 is an explanatory diagram showing a recording method applied toa BD-R recording medium;

FIG. 14 shows a flowchart referred to in explanation of a formattingprocess;

FIG. 15 is an explanatory diagram showing a process to set an SA area;

FIG. 16 is an explanatory diagram showing a process to set an SA area;

FIG. 17 shows a flowchart referred to in explanation of write processingcarried out by the recording/reproduction mechanism section shown inFIG. 3;

FIG. 18 is an explanatory diagram showing write processing carried outby the recording/reproduction mechanism section shown in FIG. 3;

FIG. 19 is an explanatory diagram showing another configuration of therecording/reproduction mechanism section;

FIG. 20 shows a flowchart referred to in explanation of write processingcarried out by the recording/reproduction mechanism section shown inFIG. 19;

FIG. 21 is an explanatory diagram showing the write processing carriedout by the recording/reproduction mechanism section shown in FIG. 19;

FIG. 22 is an explanatory diagram showing a further configuration of therecording/reproduction mechanism section;

FIG. 23 shows a flowchart referred to in explanation of write processingcarried out by the recording/reproduction mechanism section shown inFIG. 22;

FIG. 24 is an explanatory diagram showing the write processing carriedout by the recording/reproduction mechanism section shown in FIG. 22;

FIG. 25 is an explanatory diagram showing a still further configurationof the recording/reproduction mechanism section;

FIG. 26 shows a flowchart referred to in explanation of write processingcarried out by the recording/reproduction mechanism section shown inFIG. 25;

FIG. 27 is an explanatory diagram showing the write processing carriedout by the recording/reproduction mechanism section shown in FIG. 25;

FIG. 28 is an explanatory diagram showing a still further configurationof the recording/reproduction mechanism section;

FIG. 29 shows a flowchart referred to in explanation of write processingcarried out by the recording/reproduction mechanism section shown inFIG. 28;

FIG. 30 is an explanatory diagram showing the write processing carriedout by the recording/reproduction mechanism section shown in FIG. 28;

FIG. 31 is an explanatory diagram showing a still further configurationof the recording/reproduction mechanism section;

FIG. 32 shows a flowchart referred to in explanation of write processingcarried out by the recording/reproduction mechanism section shown inFIG. 31;

FIG. 33 is an explanatory diagram showing the write processing carriedout by the recording/reproduction mechanism section shown in FIG. 31;

FIG. 34 is an explanatory diagram showing the write processing carriedout by the recording/reproduction mechanism section shown in FIG. 31;

FIG. 35 shows a flowchart referred to in explanation ofalternation-information management processing carried out by therecording/reproduction mechanism section shown in FIG. 3;

FIG. 36 is an explanatory diagram showing the alternation-informationmanagement processing carried out by the recording/reproductionmechanism section shown in FIG. 3;

FIG. 37 is an explanatory diagram showing the alternation-informationmanagement processing carried out by the recording/reproductionmechanism section shown in FIG. 3;

FIG. 38 is an explanatory diagram showing the alternation-informationmanagement processing carried out by the recording/reproductionmechanism section shown in FIG. 3;

FIG. 39 shows a flowchart referred to in explanation of an actualrecording process carried out by the recording/reproduction mechanismsection shown in FIG. 3;

FIG. 40 is an explanatory diagram showing the actual recording processcarried out by the recording/reproduction mechanism section shown inFIG. 3;

FIG. 41 is an explanatory diagram showing the actual recording processcarried out by the recording/reproduction mechanism section shown inFIG. 3;

FIG. 42 shows a flowchart referred to in explanation of another actualrecording process carried out by the recording/reproduction mechanismsection shown in FIG. 3;

FIG. 43 is an explanatory diagram showing the other actual recordingprocess carried out by the recording/reproduction mechanism sectionshown in FIG. 3;

FIG. 44 shows a flowchart referred to in explanation of an actualrecording process, which is carried out by the recording/reproductionmechanism section shown in FIG. 3 when a recording medium is mounted onthe recording/reproduction apparatus employing therecording/reproduction mechanism section;

FIG. 45 is an explanatory diagram showing the actual recording process,which is carried out by the recording/reproduction mechanism sectionshown in FIG. 3 when a recording medium is mounted on therecording/reproduction apparatus employing the recording/reproductionmechanism section;

FIG. 46 shows a flowchart referred to in explanation of an SA-settingprocess carried out by the recording/reproduction mechanism sectionshown in FIG. 3;

FIG. 47 is an explanatory diagram showing the SA-setting process carriedout by the recording/reproduction mechanism section shown in FIG. 3;

FIG. 48 is an explanatory diagram showing a further configuration of therecording/reproduction mechanism section;

FIG. 49 shows a flowchart referred to in explanation of an optimizationprocess carried out by the recording/reproduction mechanism sectionshown in FIG. 48;

FIG. 50 is an explanatory diagram showing the optimization processcarried out by the recording/reproduction mechanism section shown inFIG. 48;

FIG. 51 is an explanatory diagram showing the optimization processcarried out by the recording/reproduction mechanism section shown inFIG. 48;

FIG. 52 is an explanatory diagram showing the optimization processcarried out by the recording/reproduction mechanism section shown inFIG. 48;

FIG. 53 is an explanatory diagram showing the optimization processcarried out by the recording/reproduction mechanism section shown inFIG. 48;

FIG. 54 is an explanatory diagram showing the optimization processcarried out by the recording/reproduction mechanism section shown inFIG. 48;

FIG. 55 shows a flowchart referred to in explanation of an area divisionprocess carried out by the recording/reproduction mechanism sectionshown in FIG. 48;

FIG. 56 is an explanatory diagram showing the area division processcarried out by the recording/reproduction mechanism section shown inFIG. 48;

FIG. 57 is an explanatory diagram showing the area division processcarried out by the recording/reproduction mechanism section shown inFIG. 48;

FIG. 58 shows a flowchart referred to in explanation of an area divisionprocess carried out by the recording/reproduction mechanism sectionshown in FIG. 48 as a process to allocate an area to a mirror FS; and

FIG. 59 is an explanatory diagram showing the area division processcarried out by the recording/reproduction mechanism section shown inFIG. 48 as a process to allocate an area to a mirror FS.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Before preferred embodiments of the present invention are explained,relations between disclosed inventions and the embodiments are explainedin the following comparative description. It is to be noted that, evenif there is an embodiment described in this specification but notincluded in the following comparative description as an embodimentcorresponding to an invention, such an embodiment is not to beinterpreted as an embodiment not corresponding to an invention.Conversely, an embodiment included in the following comparativedescription as an embodiment corresponding to a specific invention isnot to be interpreted as an embodiment not corresponding to an inventionother than the specific invention.

In addition, the following comparative description is not to beinterpreted as a comprehensive description covering all inventionsdisclosed in this specification. In other words, the followingcomparative description by no means denies existence of inventionsdisclosed in this specification but not included in claims as inventionsfor which a patent application is filed. That is to say, the followingcomparative description by no means denies existence of inventions to beincluded in a separate application for a patent, included in anamendment to this specification or added in the future.

An information-recording apparatus according to an embodiment of thepresent invention includes track division means (for example, a divisionsection 431 c shown in FIG. 48) wherein, when a track set on a recordingmedium as a track allocated to FSes no longer has a free area, on thebasis of a command, the area division section divides a track allocatedon the recording medium in advance to files into an area to be used as atrack allocated to FSes and an area to be used as a track allocated tofiles.

An information-recording method according to an embodiment of thepresent invention includes a track division step (for example, stepsS331 to S333 of a flowchart shown in FIG. 55 or steps S351 to S353 of aflowchart shown in FIG. 58) at which, when a track set on a recordingmedium as a track allocated to FSes no longer has a free area, on thebasis of a command, a track allocated on the recording medium in advanceto files is divided into an area to be used as a track allocated to FSesand an area to be used as a track allocated to files.

It is to be noted that since a program according to an embodiment of thepresent invention is a program prescribing the information-recordingmethod and a program storage medium according to an embodiment of thepresent invention is a medium used for storing the program, descriptionsof the program and the program storage medium are not given.

FIG. 2 is a block diagram showing the configuration of an embodimentimplementing a recording/reproduction apparatus 1 to which the presentinvention is applied.

A CPU (Central Processing Unit) 11 carries out various kinds ofprocessing by execution of programs stored in a ROM (Read Only Memory)12 or programs loaded from a storage section 18 into a RAM (RandomAccess Memory) 13. The RAM 13 is also used for properly storing variouskinds of information such as data required in execution of theprocessing and program to be executed by the CPU 11. The CPU 11, the ROM12 and the RAM 13 are connected to each other by a bus 14.

The CPU 11 is connected to an input/output interface 15 through the bus14. The input/output interface 15 is connected to an input section 16and an output section 17. The input section 16 includes a keyboard, amouse and a microphone whereas the output section 17 includes a displayunit and a speaker. The CPU 11 carries out various kinds of processingin accordance with commands entered via the input section 16. Then, theCPU 11 outputs information such as an image and/or a sound, which areobtained as results of the processing, to the output section 17.

The storage section 18 also connected to the input/output interface 15typically includes a hard disk used for storing programs to be executedby the CPU 11 and data required in the execution of the programs. Acommunication section 19 also connected to the input/output interface 15is a unit for communicating with external information-processingapparatus such as external server by way of a network mainly representedby the typical network such as the Internet and the Intranet.

As described above, the storage section 18 is used for storing programsto be read out and executed by the CPU 11 in order to carry out variouskinds of processing. Typically, the programs stored in the storagesection 18 include a basic program referred to as an OS (OperatingSystem) and device drivers. The programs stored in the storage section18 may also include a program acquired from the network by way of thecommunication section 19.

An image/audio codec 20 is a unit for carrying out a predetermineddecompression process on an image or sound file and outputting a resultof the decompression process to an external connection I/F (interface)21 and the output section 17. A file subjected to the decompressionprocess is a file read out by a drive 30 from a magnetic disk 41, anoptical disk 42, a magneto-optical disk 43 or a semiconductor memory 44.The magnetic disk 41, the optical disk 42, the magneto-optical disk 43or the semiconductor memory 44 is a recording medium mounted on thedrive 30 also connected to the input/output interface 15. As analternative, a file subjected to the decompression process is a fileread out from a recording medium 81 mounted on a recording/reproductionmechanism section 22 as shown in FIG. 3. The file subjected to thedecompression process is a file already completing a compression processadopting a predetermined compression method. In addition, theimage/audio codec 20 also compresses image and/or sound signals, whichare received from the input section 16 and the external connectioninterface 21, by adoption of a predetermined compression method. Theimage/audio codec 20 then outputs a result of the compression process tothe magnetic disk 41, optical disk 42, magneto-optical disk 43 orsemiconductor memory 44 mounted on the drive 30 or the recording medium81 mounted on the recording/reproduction mechanism section 22 as shownin FIG. 3.

The recording medium 81 mounted on the recording/reproduction mechanismsection 22 as shown in FIG. 3 is a magneto-optical recording medium suchas the Blu-ray Disc (trademark). The recording/reproduction mechanismsection 22 writes predetermined information onto the recording medium 81and reads out information from the recording medium 81. It is to benoted that a detailed configuration of the recording/reproductionmechanism section 22 will be described later by referring to FIG. 3.

When a magnetic disk 41, a optical disk 42, a magneto-optical disk 43 ora semiconductor memory 44 is mounted on the drive 30 also connected tothe input/output interface 15, the drive 30 drives the magnetic disk 41,the optical disk 42, the magneto-optical disk 43 or the semiconductormemory 44, acquiring a program and/or data from the magnetic disk 41,the optical disk 42, the magneto-optical disk 43 or the semiconductormemory 44. If necessary, the acquired program and/or data is thentransferred to the storage section 18 to be stored in the storagesection 18.

Next, the operation of the recording/reproduction apparatus 1 shown inFIG. 2 is explained.

When a command entered from the input section 16 requests that inputdata supplied by way of the external connection interface 21 be recordedonto the recording medium 81 mounted on the recording/reproductionmechanism section 22 as will be described later by referring to FIG. 3,the CPU 11 controls the image/audio codec 20 by execution of a programstored in the ROM 12, the RAM 13 or the storage section 18 to compressthe input data in accordance with a predetermined compression method andsupply the compressed data to the recording/reproduction mechanismsection 22 to be recorded onto the recording medium 81.

When a command entered from the input section 16 requests that data bereproduced from the recording medium 81 mounted on therecording/reproduction mechanism section 22, on the other hand, the CPU11 executes a program stored in the ROM 12, the RAM 13 or the storagesection 18 to control the recording/reproduction mechanism section 22 inorder to reproduce the data from the recording medium 81 and supply thereproduced data to the image/audio codec 20 and control the image/audiocodec 20 in order to decompress the reproduced data in accordance with apredetermined decompression method and output the decompressed data toan external apparatus or the output section 17 for displaying an imageof the data and/or generating a sound of the data.

Next, the detailed configuration of the recording/reproduction mechanismsection 22 is explained by referring to FIG. 3.

A control section 51 is a unit for controlling all operations of therecording/reproduction mechanism section 22. To be more specific, on thebasis of a control signal received from the CPU 11, the control section51 controls a recording section 52 to drive a recording/reproductionblock 53 in order to record information onto the recording medium 81 orcontrols a reproduction section 54 to drive the recording/reproductionblock 53 in order to read out information from the recording medium 81.

A file-system information generation section 62 employed in the controlsection 51 is a unit for determining a recording location on therecording medium 81 on the basis of the attribute of a file received asinput data also including the attribute and recording the file at thedetermined recording location since such files are grouped by thefile-system information generation section 62 by file attribute. Inaddition, on the basis of pieces of information included in the inputdata, the file-system information generation section 62 also generatesfile-system information and supplied the information to the recordingsection 52 to be recorded onto the recording medium 81. The file-systeminformation generation section 62 records file-system information,anchor information and information on the structure of the volume ineither of a user area and an SA area (Spare Area), which exist on therecording medium 81. An initialization section 62 a employed in thefile-system information generation section 62 is a unit, which is usedfor setting a recording area and an SA area (or a disk management area)including a TDMA (Temporary Defect Management Area) and analternate-sector area when the recording medium 81 is formatted. When asector on the recording medium 81 is damaged physically, an alternatesector is used as a substitute for the damaged sector, into whichinformation supposed to be recorded in the damaged sector is recorded.Even if the physical recording address of the alternate sector on therecording medium 81 is different from the physical recording address ofthe damaged sector, a logical address assigned to the recordedinformation remains unchanged. Thus, the use of the alternate sectordoes not affect an operation to record the information into thealternate sector by using the logical address and an operation to readout the information from the alternate sector by using the logicaladdress. In a process to incrementally write information in a fileexisting on the disk or update a file already existing on the disk, thefile-system information generation section 62 employed in the controlsection 51 controls a write section 73 to record file-systeminformation, anchor information and information on the structure of thevolume in an SA area serving as an alternate area. The TDMA is an area,which is used for incrementally recorded alternate managementinformation when an alternate process is carried out to renew data orcarried out in the event of a detected defect. It is to be noted that,in descriptions by referring to the subsequent drawings up to FIG. 45,the TDMA and the alternate-sector area are referred to merely as an SAarea or an alternate-sector area. Detailed descriptions including anexplanation of the TDMA are given later with reference to FIG. 46 andsubsequent figures.

A file-system information recognition section 61 employed in the controlsection 51 is a unit for reading out either of main file-systeminformation and mirror file-system information, which are supplied fromthe reproduction section 54, and reading out a predetermined file on thebasis of this file-system information. To put it in more detail, thefile-system information recognition section 61 controls a read section91 to read out file-system information, information on the structure ofthe volume and anchor information from either the user area or an SAarea. It is to be noted that, in a process to record information ontothe recording medium 81 in the recording/reproduction mechanism section22 shown in FIG. 3, the same file-system information is also recorded attwo locations as main file-system information and mirror file-systeminformation respectively in a double-information structure so that, evenif one of the main file-system information and the mirror file-systeminformation is damaged due to some reasons, the remaining one in thedouble-information structure can still be used. It is also worth notingthat, in the following descriptions, the main file-system informationand the mirror file-system information are referred to as a main FS anda mirror FS respectively.

If a write process is a process to renew existing data with new data, analternation-information management section 63 stores an originallocation and an alternate location in a memory 63 a for each logicaladdress by associating the locations with each other in the form of a DL(Defect List). A logical address is assigned to every cluster. Theoriginal location is a location at which the data to be renewed exists.On the other hand, the alternate location is a replacement location atwhich the new data is actually recorded.

In a process to record data onto the recording medium 81, analternation-information generation section 64 reads out the DL from thememory 63 a employed in the alternation-information management section63 to find out whether or not the data should be written at an alternatelocation instead of a defective original location. If informationincluded on the DL as information associating an original location withan alternate location at an information granularity corresponding to acluster indicates that the data should be written at alternate locationsof contiguous clusters, the alternation-information generation section64 replaces the original locations of the contiguous original clusterson the DL with one original location and the alternate locations of thecontiguous alternate clusters on the DL with one alternate location,recording the data at the alternate locations of the contiguous clustersas single data.

If the alternation-information generation section 64 reads out the DLfrom the memory 63 a employed in the alternation-information managementsection 63 in a process to record data onto the recording medium 81 onlyto find out that information included on the DL as informationassociating an original location with an alternate location at aninformation granularity corresponding to a cluster indicates that thedata should be written at alternate locations of non-contiguousclusters, on the other hand, the alternation-information generationsection 64 changes a plurality of alternate locations on the DL tocollect them in a single alternate location representing contiguousclusters and records the data as single data in the contiguous clusters,which are registered as a single entry on the DL.

A recording/reproduction block 53 is a unit controlled by the writesection 73 to physically record information onto the recording medium 81and controlled by the read section 91 to physically reproduceinformation from the recording medium 81. The recording medium 81 is amedium onto which information can be recorded mechanically, optically,magnetically or opto-magnetically. The recording medium 81 may be amedium onto which information can be recorded repeatedly or only once.Examples of the medium onto which information can be recorded repeatedlyare a BD-RW (Blu-ray Disc-Rewritable), a DVD-RW (Digital VersatileDisc-Rewritable) and a DVD-RAM (Digital Versatile Disc-Random AccessMemory). On the other hand, examples of the medium onto whichinformation can be recorded only once are a BD-R (Blu-rayDisc-Recordable) and a DVD-R (Digital Versatile Disc-Recordable). Inaddition, the recording medium 81 may also be a DVD-ROM (DigitalVersatile Disc-Read Only Memory). The recording medium 81 can be anytype of medium as long as the medium is a disk-type recording mediumallowing data to be read out from and data to be recorded thereon.Accordingly, the recording/reproduction block 53 can be any type of unitcapable of reproducing data from such a recording medium 81 andrecording data thereon.

An ECC encoding section 71 is a unit for adding an error correction codeto an input, encoding the input and the additional error correction codeand outputting a result of the encoding process to a modulation section72. The modulation section 72 is a unit for modulating data receivedfrom the ECC encoding section 71 and outputting a result of themodulation process to the write section 73. The write section 73 is aunit for carrying out a write process to supply data received from themodulation section 72 to the recording/reproduction block 53 forrecording the data onto the recording medium 81.

The read section 91 employed in the reproduction section 54 is a unitfor reading out information recorded on the recording medium 81. Ademodulation section 92 employed in the reproduction section 54 is aunit for demodulating data read out by the read section 91 from therecording medium 81 and outputting the result of the demodulationprocess to an ECC decoding section 93 employed in the reproductionsection 54. The ECC decoding section 93 is a unit for splitting datareceived from the demodulation section 92 into an ordinary file andfile-system information and outputting the ordinary file as output dataand the file-system information to the control section 51. The ordinaryfile typically contains AV (Audio Visual) stream data.

By referring to FIG. 4, the following description explains a managementstructure of input-data files, which are grouped and managed by thefile-system information generation section 62 employed in the controlsection 51. It is to be noted that files are recorded on the recordingmedium 81 basically in a UDF format. Thus, in accordance with themanagement structure described below, files are recorded on therecording medium 81 in the UDF format.

FIG. 4 is a diagram showing a typical case of managing a variety of datafiles in a process of recording AV stream data onto a recording mediumallowing data already recorded thereon to be renewed. The managementstructure conforms to the management structure of the specifications ofthe Blu-ray Disc Rewritable (trademark). To put it in detail, themanagement structure conforms to the management structure of thespecifications of the Blu-ray Disc Rewritable (trademark), but therecording format is the UDF format. In the example shown in FIG. 4,three layers are shown. The three layers are a content management layerexisting on the top of the figure to be followed sequentially by aplay-list layer and a clip layer. It is to be noted that this managementstructure is also applicable to the Blu-ray Disc Recordable (trademark).

In the management structure shown in the figure, a play-list managementtable 111 and a thumbnail management table 112 pertain to the contentmanagement layer whereas play lists 113-1 to 113-3 pertain to theplay-list layer. By the same token, pieces of clip information 121-1 to121-3 pertain to the clip layer. It is to be noted that, in thefollowing description, the play lists 113-1 to 113-3 are each referredto merely as a play list 113 if it is not necessary to distinguish theplay lists 113-1 to 113-3 from each other. By the same token, the piecesof clip information 121-1 to 121-3 are each referred to merely as clipinformation 121 if it is not necessary to distinguish the pieces of clipinformation 121-1 to 121-3 from each other. This representation using ageneric reference numeral applies to each plurality of any other similarmanagement-structure items.

The file of an AV stream 131 and the file of clip information 121 can becombined to particularly form a clip since the file of clip information121 has an attribute of an AV stream. An example of the AV stream 131 isMPEG-TS (Moving Picture Experts Group—Transport Stream). The file of anAV stream 131 is thus a file having a structure of multiplexedinformation including video information, audio information and captions.In addition, in some cases, the multiplexed information of an AV stream131 may include a command for controlling a reproduction process. Thefigure shows a case in which the AV stream 131 includes such a commandin the multiplexed information.

A play list 113 for a clip has a structure including a plurality of playitems each to be referenced by using a reproduction start point and areproduction end point, which define a specific range of the clip. Thus,a play list 113 provides a function to continuously reproduce aplurality of reproduction sequences. The play-list management table 111is a table showing a list of play lists 113 to the user. On the otherhand, the thumbnail management table 112 is a table to be used in athumbnail display function. The thumbnail management table 112 showsthumbnail files 141-1 and 141-2 as well as thumbnail files 151-1 and151-2.

A pair of an AV stream 131 and the attribute thereof is regarded as anobject, which is referred to as a clip. The attribute of an AV stream131 is the clip information 121 mentioned earlier. The file of an AVstream 131 is referred to as an AV-stream file.

In general, a file used in apparatus such as a computer is treated as anarray of bytes. The content of an AV stream 131 is spread along the timeaxis. An access point of clip information 121 in an AV stream 131 ismainly specified by using a timestamp. With a play list 113 giving atimestamp as the timestamp of an access point of a clip corresponding tothe play list 113, the clip information 121 corresponding to the playlist 113 is used for finding out an address at which a process to decodethe stream in the AV stream 131 is to be started. The address indicatesthe location of a byte on the stream.

A play list 113 is a list introduced for the purposes of allowing theuser to find out a reproduction range of a clip corresponding to theplay list 113 as a range that the user wants to view and allowing suchreproduction ranges to be edited with ease. A play list 113 is acollection of reproduction ranges in a clip corresponding to the playlist 113. A reproduction range of a clip is referred to as a play item,which is represented by IN and OUT points on the time axis. Thus, a playlist 113 is a collection of play items.

In the example shown in FIG. 4, files are divided into groups inaccordance with their usage/updating frequencies and the maximum totalsize of files pertaining to a group as follows. The play-list managementtable 111, the thumbnail management table 112 and the play lists 113 areput in group 1 whereas the pieces of information 121 are put in group 2.Menu thumbnail files 141-1 and 141-2 are put in group 3 whereas markthumbnail files 151-1 and 151-2 are put in group 4.

The files grouped as described above contain management data required ina process to reproduce an AV stream 131. By collecting pieces ofmanagement data in a file grouped as described above, the managementdata can be read out fast. As a result, the AV stream data can bereproduced at a high speed.

In the typical example described above, files of management data for anAV stream 131 are grouped. It is to be noted that files not defined inthe specifications of the Blu-ray Disc Rewritable can also be grouped.For example, group X is defined as a group for accommodating files 161-1and 161-2 different from the files of management data for AV streams 131shown in the figure. It is also worth noting that the figure shows files171-1 and 171-2 pertaining to none of the groups. In addition, since theAV streams 131 are not management data, the AV streams 131 are notgrouped.

FIG. 5 is a diagram showing a typical structure of directories for BDAV(Blu-ray Disc Audio Visual) information recorded on the recording medium81 as information defined by a Blu-ray Disc Rewritable Format (BD-RE).It is to be noted that directories other than those shown in the figurecan be created under a root directory shown in the figure. However, suchother directories are ignored in a recording process conforming to theUDF format. The directory structure shown in FIG. 5 is also applicableto a BD-R (Blu-ray Disc Recordable).

As shown in the figure, the root directory includes only one directorynamed BDAV.

All files and directories included in the BDAV directory are files anddirectories prescribed by a BDAV application format. In addition, theBDAV directory also includes directory described as follows.

A PLAYLIST directory is a directory, which includes database files ofplay lists 113. This directory is set as an empty directory even if playlists 113 do not exist at all.

A CLIPINF directory is a directory, which includes database files ofclips. This directory is set as an empty directory even if clips do notexist at all.

A STREAM directory is a directory, which includes AV stream files. Thisdirectory is set as an empty directory even if AV stream files do notexist at all.

A BACKUP directory is a directory, which includes backup files of filespertaining to groups 1 and 2. This directory is set even if the filespertaining to groups 1 and 2 do not exist at all.

The play list files included in the PLAYLIST directory are files of oneof 2 types, i.e., Real PlayList and Virtual PlayList. In the exampleshown in FIG. 5, files 1111.rpls of the Real PlayList type and22222.vpls of the Virtual PlayList type are recorded. In general, a filenamed xxxxx.rpls is used for storing information on a Real PlayList andcreated for every play list. Notation xxxxx in the file name xxxxx.rplsis a 5-digit number where each digit can be any integer in the range 0to 9.

On the other hand, a file named yyyyy.vpls is used for storinginformation on a Virtual PlayList and created for every play list.Notation yyyyy in the file name yyyyy.vpls is a 5-digit number whereeach digit can be any integer in the range 0 to 9.

A Real Playlist for a clip is regarded as a file sharing a streamportion of the clip being referenced. That is to say, a Real Playlistoccupies a disk area with a data storage size corresponding to the AVstream portion of a clip being referenced. When an AV stream is recordedas a new clip, a Real Playlist is generated as a play list referencingthe reproducible range of the entire clip. If a portion of thereproduction range of a Real Playlist is deleted, the data of the clipstream portion referenced by the deleted portion is also deleted aswell.

On the other hand, a Virtual Playlist for a clip is regarded as a filesharing no data of the clip. Thus, even if a Virtual Playlist is changedor deleted, the clip does not change at all. It is to be noted that, inthe description of this specification, the Real Playlist and the VirtualPlaylist are both referred to as a play list.

The CLIPINF directory includes a file for every AV stream file. In theexample shown in FIG. 5, the files included in the CLIPINF directory arefiles named 01000.clpi and 02000.clpi.

A file named zzzzz.clpi is clip information 121 corresponding to an AVstream 131. Notation zzzzz in the file name zzzzz.clpi is a 5-digitnumber where each digit can be any integer in the range 0 to 9.

As described above, the STREAM directory is a directory, which includesAV stream files. In the example shown in FIG. 5, the files included inthe STREAM directory are files named 01000.m2ts and 02000.m2ts.

In general, a file named zzzzz.m2ts is the file of an AV stream 131.Notation zzzzz in the file name zzzzz.m2ts is a 5-digit number whereeach digit can be any integer in the range 0 to 9. It is to be notedthat the clip information 121 corresponding to an AV stream 131 isstored in a file having the same 5-digit family name zzzzz as the filename given to the file for storing the AV stream 131.

In addition, the BDAV directory also includes files named menu1.tdt andmenu2.tdt for the thumbnail files 141-1 and 141-2 respectively as directsubordinates to the BDAV directory. Furthermore, the BDAV directory alsoincludes files named mark1.tdt and mark2.tdt for the thumbnail files151-1 and 151-2 respectively as direct subordinates to the BDAVdirectory. Moreover, as direct subordinates to the BDAV directory, theBDAV directory also includes a file named info.bdav for the play-listmanagement table 111 as well as files named menu.tidx and mark.tidx forthe thumbnail management table 112.

On top of that, the root directory also includes directories named DATA1and DATA2 as direct subordinates to the root directory. The DATA1directory accommodates File1.dat, File2.dat, etc corresponding torespectively the files 161-1, 161-2, etc. On the other hand, the DATA2directory accommodates FileA.dat, FileB.dat, etc corresponding torespectively the files 171-1, 171-2, etc.

The files and the directories managed under the directory shown in FIG.5 are put in groups shown in FIG. 4 as follows. The files namedmenu1.tdt and menu2.tdt as files corresponding to the thumbnail files141-1 and 141-2 respectively pertain to group 3. The files namedmark1.tdt and mark2.tdt as files corresponding to the thumbnail files151-1 and 151-2 respectively pertain to group 4. The file namedinfo.bdav for the play-list management table 111, the files namedmenu.tidx and mark.tidx for the thumbnail management table 112 as wellas the files named 11111.rpls and 22222.vpls as files accommodated inthe PLAYLIST directory pertain to group 1. The files named 01000.clpiand 02000.clpi as files accommodated in the CLIPINF directory pertain togroup 2.

As described above, files other than those managed by using the BDFS areput in group X. In the example shown in FIG. 5, the other files are thefiles named File1.dat and File2.dat in the DATA1 directory as filescorresponding to the files 161-1 and 161-2 respectively.

FIGS. 4 and 5 show management structures for grouping of files recordedon the recording medium 81 in accordance with the UDF format and on thebasis of the specifications of the Blu-ray Disc Rewritable, which is arecording medium allowing data recorded thereon to be rewritten. Byreferring to FIGS. 6 and 7, the following description explains typicalmanagement structures (or a typical logical format) for grouping offiles recorded on the recording medium 81 on the basis of thespecifications of the Blu-ray Disc ROM, which is a read-only recordingmedium. FIG. 6 is a diagram showing a typical case of recording an HD(High Density) movie content.

It is to be noted that, in the example shown in FIG. 6, play lists 221-1to 221-3, pieces of clip information 231-1 to 231-3, AV streams 232-1 to232-3, files 251-1 and 251-2 as well as files 261-1 and 261-2 areidentical to respectively the play lists 113-1 to 113-3, the pieces ofclip information 121-1 to 121-3, the AV streams 131-1 to 131-3, thefiles 161-1 and 161-2 as well as the files 171-1 and 171-2 shown in FIG.4. Thus, descriptions of them are not given.

As shown in FIG. 6, two layers exist over the play lists 221 and thepieces of clip information 231. One of the layers is a layer foraccommodating reproduction programs (or movie objects) 221-1 and 221-2.The other layer is a layer for accommodating titles 201 and 202. Thereproduction program (or the movie object) 211 provides programmablefunctions, which are required for presentation of an HD movie content.The functions include a function to specify a play list to bereproduced, a function to respond to an operation carried out by theuser, a function to jump from the title 201 to the title 202 or viceversa and a function to carry out a branch in a reproduction sequence.

The titles 201 and 202 are each used as an index, which can berecognized by the user as an index for starting reproduction of acontent corresponding to the title. The titles 201 and 202 each have aconfiguration for specifying one movie object to be executed. Inaddition to ordinary titles, there are also a title to be reproducedautomatically at an initial time and a title used for displaying a menu.

Application programs 203 and 204 are each a program for executing agame, which is an extension application, and a web content. Theapplication programs 203 and 204 activate and execute reproductionprograms (or reproduction objects) 212-1 and 212-2. The reproductionprogram 212 can be a program using a play list or a program not using aplay list. In addition, the reproduction program 212 is capable ofreferencing any arbitrary image file 241, audio file 242 and data file243 in the application programs 203 and 204.

It is possible to add more titles to the titles 201 and 202 each showingan HD movie content and more applications to the applications 202 and203. As a matter of fact, others 205 in the example shown in FIG. 6represent the additional titles and applications. In addition, thetitles and the applications are recorded on the recording medium 81 in astate of being mixed with each other. FIG. 6 shows this state of mixingthe titles and the applications with each other.

Also in the example shown in FIG. 6, files are divided into groups inaccordance with their usage/updating frequencies and the maximum totalsize of files pertaining to a group in the same way as the groupingshown in FIG. 4. To put it concretely, the titles 201 and 202, theapplications 203 and 204, the others 205, the reproduction programs211-1, 211-2, 212-1 and 212-2 as well as the play lists 221-1 to 221-3are put in group A. The pieces of clip information 231 are put in groupB. The image files 241, the audio files 242 and the data files 243 areput in group C.

It is to be noted that groups A, B and C shown in FIG. 6 are providedand named differently from each other only for the sake of conveniencein the same way as groups 1, 2, 3 and 4 shown in FIG. 4. Also in thiscase, each of the groups means a set of files to be processed in thesame way as those shown in FIG. 4.

FIG. 7 is a diagram showing a typical structure of directories for BDMV(Blu-ray Disc Movie) information recorded on the recording medium 81 asinformation defined by a Blu-ray Disc ROM Format (BD-ROM). It is to benoted that directories other than those shown in the figure can becreated under a root directory shown in the figure. However, such otherdirectories are ignored in a recording process conforming to the UDFformat.

As shown in the figure, the root directory includes only one directorynamed BDMV.

All files and directories included in the BDMV directory are files anddirectories prescribed by a BDMV application format. In addition, theBDMV directory also includes directory described as follows.

A PLAYLIST directory is a directory, which includes database files ofplay lists 221. This directory is set as an empty directory even if playlists 221 do not exist at all.

A CLIPINF directory is a directory, which includes database files ofclips. This directory is set as an empty directory even if clips do notexist at all.

A STREAM directory is a directory, which includes AV stream files. Thisdirectory is set as an empty directory even if AV stream files do notexist at all.

A BACKUP directory is a directory, which includes backup files of filespertaining to groups A and B. This directory is set as an emptydirectory even if the files pertaining to groups A and B do not exist atall.

In the example shown in FIG. 7, files 11111.rpls and 22222.rpls areaccommodated in the PLAYLIST directory. In general, a file namedxxxxx.rpls is used for storing information on a Movie PlayList andcreated for every play list. Notation xxxxx in the file name xxxxx.rplsis a 5-digit number where each digit can be any integer in the range 0to 9.

The CLIPINF directory includes a file for every AV stream file. In theexample shown in FIG. 7, the files included in the CLIPINF directory arefiles named 01000.clpi and 02000.clpi.

A file named zzzzz.clpi is clip information 231 corresponding to an AVstream 232. Notation zzzzz in the file name zzzzz.clpi is a 5-digitnumber where each digit can be any integer in the range 0 to 9.

As described above, the STREAM directory is a directory, which includesAV stream files. In the example shown in FIG. 7, the files included inthe STREAM directory are files named 01000.m2ts and 02000.m2ts.

In general, a file named zzzzz.m2ts is the file of an AV stream 232.Notation zzzzz in the file name zzzzz.m2ts is a 5-digit number whereeach digit can be any integer in the range 0 to 9. It is to be notedthat the clip information 231 corresponding to an AV stream 232 isstored in a file having the same 5-digit family name zzzzz as the filename given to the file for storing the AV stream 232.

In addition, the BDMV directory also includes filesUnit_Key_Gen_Value.inf and CPS_CCI.inf related to copy control as directsubordinates to the BDMV directory. Furthermore, direct subordinates tothe BDMV directory also include a file named index.bdmv serving as atitle management table. Moreover, direct subordinates to the BDMVdirectory also include a file named MovieObject.bdmv serving as areproduction-program management table.

On top of that, the root directory also includes directories namedResource, DATA1 and DATA2 as direct subordinates to the root directory.These directories are not mandatory directories in the Blu-ray Disc ROMformat. Instead, these directories are merely added as typicaldirectories each used for storing extension data, which is necessary independence on the substance of the content. The Resource directory is adirectory used for accommodating the image file 241 named Image.jpg, theaudio file 242 named Audio.pcm and the data file 243 named Jimaku.txt.The image file 241, the audio file 242 and the data file 243 are filesmanaged by including them in group C. The DATA1 directory accommodatesFile1.dat, File2.dat, etc corresponding to respectively the files 251-1,251-2, etc. On the other hand, the DATA2 directory accommodatesFileA.dat, FileB.dat, etc corresponding to respectively the files 261-1,261-2, etc.

The files and the directories managed under the directory shown in FIG.7 are put in groups as follows. The files named Unit_Key_Gen_Value.inf,CPS_CCI.inf, index.bdmv and MovieObject.bdmv pertain to group A. Filesaccommodated in the PLAYLIST directory as the files named 11111.mpls and22222.mpls also pertain to group A. Files accommodated in the CLIPINFdirectory as the files named 01000.clpi and 02000.clpi pertain to groupB. Files accommodated in the Resource directory as the files namedImage.jpg, Audio.pcm and Jimaku.txt pertain to group C.

As described above, files other than those managed by using the groupsdescribed above are put in group X. In the example shown in FIG. 7, theother files are the files named File1.dat and File2.dat in the DATA1directory as files corresponding to the files 251-1 and 251-2respectively.

Next, before explaining a recording process according to an embodimentof the present invention, a procedure for making an access to a file inthe conventional UDF is described by referring to FIGS. 8 and 9.

FIG. 8 is a diagram showing a typical volume structure of the UDF. FIG.9 is a diagram showing the contents of a File Structure and Files. Inparticular, the following description explains an access toroot/BDMV/Unit_Key_Gen_Value.inf shown in FIG. 9.

The volume structure shown in FIG. 8 includes information on a logicalvolume and information on the analysis start point of each filestructure recorded in a partition. It is to be noted that, in the volumestructure shown in FIG. 8, the left-most column is an LSN (LogicalSector Number) column. On the right side of the LSN column, there is astructure column, which is followed by a descriptors column. Theright-most column is an LBN (Logical Block Number) column. In the filestructure shown in FIG. 9, the left-most column is an LBN column, themiddle column is a structure column and right-most column is adescriptors column.

An address in a volume is referred to as an LSN (Logical Sector Number)and an address in a partition is referred to as an LBN (Logical BlockNumber). If a plurality of partitions exists in the volume, informationon the partitions can be recorded in a logical volume descriptor.

It is to be noted that FIGS. 8 and 9 show only items required inprocessing. That is to say, items not required in processing are notdescribed.

First of all, reference numeral (1) in the volume structure shown inFIG. 8 denotes anchor information for Anchor-1 on the structure column.The information on this anchor is referred to as an Anchor VolumeDescriptor Pointer to be analyzed to obtain the position of a VolumeDescriptor Sequence denoted reference numeral (2). In the volumestructure, this anchor information is provided at a location indicatedby an LSN of 256. As described above, reference numeral (2) denotes aVolume Descriptor Sequence indicated by LSNs of 32 to 47 as a sequenceon the structure column. The Volume Descriptor Sequence corresponds toitems on the descriptors column. These items on the descriptors columnare a Primary Volume Descriptor, an Implementation Use VolumeDescriptor, a Partition Descriptor, a Logical Volume Descriptor, anUnallocated Space Descriptor, a Terminating Descriptor and TrailingLogical Sectors. The Primary Volume Descriptor is informationidentifying the volume. The Implementation Use Volume Descriptor isinformation indicating compatibility. The Partition Descriptor isinformation on partitions. The Logical Volume Descriptor is informationshowing the position of a logical partition. The Unallocated SpaceDescriptor is information indicating an unused area. The TerminatingDescriptor is information showing the last position in the area. TheTrailing Logical Sectors is information on a remaining area.

In the volume structure shown in FIG. 8, reference numeral (3) denotesthe Logical Volume Descriptor, which is provided at a location indicatedby an LSN of 35. The Logical Volume Descriptor describes the position ofa Logical Volume Integrity Sequence, the position of a target partitionand the position of a File Set Descriptor inside the partition.

The position of a Logical Volume Integrity Sequence is the position of aLogical Volume Integrity Sequence denoted by reference numeral (4) andprovided at a location indicated by an LSN of 48. The Logical VolumeIntegrity Sequence is a sequence to be analyzed to check the matching ofthe information on the volume. If there is no matching problem, thecontents of a partition for the File Structure and Files are analyzed.The File Structure and Files are an item denoted by reference numeral(5) and provided at a position indicated by LSNs of 272 to(272Nall−272). A sequence represented by arrows between referencenumerals (1) to (5) mentioned above is the sequence of a procedure forstarting to make an access to the target partition.

The File Set Descriptor mentioned above is a File Set Descriptor denotedby reference numeral (11) and provided at a position indicated by an LBNof (A+1) in the structure shown in FIG. 9. The File Set Descriptor isinformation on the root. Thus, by analyzing the information on the root,the position of the root-directory file entry denoted by referencenumeral (12) and provided at a position indicated by an LSN of (A+3) canbe obtained. In the figure, the file entry of the root directory isreferred to as an FE (Root Directory).

Then, the root-directory file entry denoted by reference numeral (12)and provided at a position indicated by an LBN of (A+3), that is, a fileentry referred to as an FE (Root Directory) in the figure, is analyzedto obtain root-directory information stored at a location indicated byan LBN of (A+4). Then, an FID (File Identifier Descriptor) of the BDMVdirectory is analyzed to obtain the position of a BDMV-directory FE(file entry) denoted by reference numeral (14) and provided at aposition indicated by an LBN of (A+5). The FID of the BDMV directory isinformation included in the information on the root directory anddenoted by reference numeral (13). In the figure, the file entry of theBDMV directory is referred to as an FE (BDMV).

Subsequently, the BDMV-directory FE (file entry) denoted by referencenumeral (14) is analyzed to obtain a location indicated by an LBN of(A+9) as a location used for storing information on the BDMV directory.

Then, the information on the BDMV directory is obtained. Subsequently,the File Identifier Descriptor of Unit_Key_Gen_Value.inf accommodated inthe BDMV dirtory and denoted by reference numeral (15) is analyzed toobtain the position of the file entry of Unit_Key_Gen_Value.inf. Then,the file entry of Unit_Key_Gen_Value.inf is analyzed to obtain alocation used for recording data of Unit_Key_Gen_Value.inf. The fileentry of Unit_Key_Gen_Value.inf is denoted by reference numeral (16).The location used for recording data of Unit_Key_Gen_Value.inf is theaddress of the data of Unit_Key_Gen_Value.inf. Subsequently, an accessto the address is made to get the desired data. A sequence representedby arrows between reference numerals (11) to (17) mentioned above is thesequence of a procedure for obtaining the data ofroot/BDMV/Unit_Key_Gen_Value.inf.

If a metadata partition introduced by UDF2.50 is used, the File SetDescriptor denoted by reference numeral (11), the root-directory FE(file entry) denoted by reference numeral (12), the BDMV-directory FID(File Identifier Descriptor) denoted by reference numeral (13), theBDMV-directory FE (file entry) denoted by reference numeral (14), theFID (File Identifier Descriptor) of Unit_Key_Gen_Value.inf accommodatedin the BDMV directory and denoted by reference numeral (15) and the fileentry of Unit_Key_Gen_Value.inf accommodated in the BDMV directory anddenoted by reference numeral (16) are relocated in the metadatapartition by using logical addresses.

The location used for recording the metadata partition can be obtainedfrom the file entry of the metadata file. By storing the data of themetadata partition in a memory, it is possible to avoid operations toread out three pieces of information, i.e., a file identifierdescriptor, a file entry and information on a directory, from therecording medium every time the directory is changed to one at a lowerlevel in a process to make an access to a file accommodated in adirectory of a multi-layer structure. This is because, from the data ofthe metadata partition, information necessary for reading out a filefrom the recording medium can be obtained and analyzed.

By referring to FIGS. 10 to 12, the following description explains atechnique of relocating file-system information at a virtual address.

The file-system information is relocated as a metadata file at alocation identified by an address in an ordinary physical partition usedin a file system. Virtual addresses are assigned to the contents of ametadata file with a virtual address of 0 corresponding to the beginningof a partition. Metadata information is constructed in a formatreferencing the virtual addresses in the metadata partition.

That is to say, by using virtual addresses in the metadata file, it ispossible to trace (read out) pieces of information including the FileSet Descriptor denoted by reference numeral (11), the root-directory FE(file entry) denoted by reference numeral (12), the BDMV-directory FID(File Identifier Descriptor) denoted by reference numeral (13), theBDMV-directory FE (file entry) denoted by reference numeral (14), theFID (File Identifier Descriptor) of Unit_Key_Gen_Value.inf accommodatedin the BDMV directory and denoted by reference numeral (15) and the fileentry of Unit_Key_Gen_Value.inf accommodated in the BDMV directory anddenoted by reference numeral (16), which have been explained earlier byreferring to FIG. 9.

In the upper diagram of FIG. 10, a block B11 is an area used forrecording an MD file FE (Metadata File File-Entry). On the basis of theMD file FE, the file-system information (FS) recorded in a block B12 canbe traced. That is to say, the MD file FE recorded in the block B11indicates that the file-system information (FS) has been recorded in theblock B12, which is an area from an address A to an address (A+X) in aphysical partition. As shown in the lower diagram of FIG. 10, on theother hand, the file-system information (FS) is recorded in an area P1,which is an area from the virtual address of 0 to a virtual address X ina metadata partition.

A metadata partition can be associated with a plurality of areas in aphysical partition. As shown in the upper diagram of FIG. 11, forexample, a metadata partition P2 is associated with two areas in aphysical partition. One of the areas is a block B23 from an address A toan address (A+X) and the other area is a block B22 from an address B toan address (B+Y). In this case, the MD file FE in the block B21indicates that the file-system information is recorded in the block B23from an address A to an address (A+X) and the block B22 from an addressB to an address (B+Y). As shown in the lower diagram of FIG. 11, thefile-system information is recorded in an area P2 from a virtual addressof 0 to a virtual address (X+Y) in a metadata partition.

In addition, an UDF2.50 function can be executed to relocate a metadatafile as a double file in order to enhance the reliability of thefile-system information. To put it concretely, the metadata file isrecorded as two identical metadata files (FS). One of the files isreferred to as a main metadata file (main FS) while the other file isreferred to as a mirror metadata file (mirror FS).

That is to say, let us assume that a main metadata file containingfile-system information is relocated in a block B32 from an address A toan address (A+X) in a physical partition as shown in the upper diagramof FIG. 12. On the other hand, a mirror metadata file containing thesame file-system information is relocated in a block B34 from an addressB to an address (B+Y) in the physical partition. In this case, the MDfile FE in a block B31 indicates that the main metadata file containingfile-system information is relocated in the block B32 from the address Ato the address (A+X) in the physical partition. In addition, as a mainmetadata file, file-system information is recorded in an area P3 from avirtual address of 0 to a virtual address X in a metadata partition asshown in the lower diagram of FIG. 12. By the same token, the MD file FEin a block B33 indicates that the mirror metadata file containing thesame file-system information is relocated in the block B34 from theaddress B to the address (B+Y) in the physical partition. In addition,in the same way as the main metadata file described above, as a mirrormetadata file, file-system information is recorded in the area P3 fromthe virtual address of 0 to the virtual address X in the metadatapartition as shown in the lower diagram of FIG. 12. By recording thesame metadata file in different areas as described above, thereliability of the file-system information can be improved.

Next, by referring to FIG. 13, the following description explains arecording method provided for a case in which the recording medium 81 isa BD-R. In the recording method applied to the BD-R, there are tworecording modes, i.e., a sequential recording mode and a randomrecording mode.

The sequential recording mode is a mode in which information is recordedsequentially onto a recording medium in a predetermined directionbeginning from a recording start position of the recording medium. Inthe case of a recording medium with a shape resembling a disc, therecording start position is the center of the disc. On the other hand,the random recording mode is a mode in which information is recordedonto a recording medium at a recording location set at random. In thecase of a recording medium with a shape resembling a disc, informationrecorded on the recording medium by adoption of the sequential recordingmode can be read out from the recording medium at a speed higher thaninformation recorded on the recording medium by adoption of the randomrecording mode. This is because, in the case of information alreadyrecorded on the recording medium by adoption of the sequential recordingmode, the recording locations reflect a relation between precedinginformation and succeeding information. The following descriptionassumes that information is recorded on a recording medium by adoptionof the sequential recording mode. However, the embodiment of the presentinvention does not limit the mode for recording information onto therecording medium to the sequential recording mode. Instead, the randomrecording mode can also be adopted as the mode for recording informationonto the recording medium.

FIG. 13 is a diagram showing an outline of the sequential recording modeadopted as the mode for recording information onto the BD-R recordingmedium.

Information is recorded into a user area on the BD-R in session units.In the example shown in FIG. 13, only two sessions, i.e., sessions 1 and2 have been recorded in the user area. It is needless to say, however,that more sessions can also be recorded. A session includes at least oneSRR (Sequential Recording Ranges). In addition, a multi-sessionrecording area may also be resulted in. In this case, however,information can be recorded into only the last set session.

An SRR (Sequential Recording Ranges) includes a plurality of 64 KBclusters, which are each the smallest recording unit of informationrecorded onto the BD-R. The SRR is a recording unit corresponding to atrack in a CD-R (Compact Disc-Recordable) medium. The SRR can be in oneof two states, i.e., open and closed states. In an open state,information can be recorded into an SRR. After information is recordedinto an SRR, the SRR is put in a closed state allowing no information tobe recorded into the SRR. A session can have up to 16 SRRs put in anopen state. A maximum of about 7,600 SRRs can be set in a BD-R. In theexample shown in FIG. 13, SRRs #1 to #5 have been set and, in areas281-1 to 281-4 of SRRs #1 to #4, pieces of data have been recorded. Theend of each of areas 281-1 to 281-4, in which the pieces of data havebeen recorded, is referred to as an LRA (Last Recording Allocation)indicating the end recording position. In addition, in the example shownin FIG. 13, SRRs #3 and #5 are each in an open state while the otherSRRs are closed. In each of SRRs #3 and #5, the LRA is immediatelyfollowed by an NWA (New Writing Allocation), which is the beginning of afree area used for newly recording information in the SRR.

Next, processing to format the recording medium 81 is explained byreferring to a flowchart shown in FIG. 14.

The flowchart begins with a step S1 at which the initialization section62 a of the file-system information generation section 62 employed inthe control section 51 controls the write section 73 to drive therecording/reproduction block 53 to carry out an SA-setting process toset an SA area (Spare Area) on the recording medium 81. Let us assumefor example that the recording medium 81 is a single-layer BD-R. In thiscase, an SA area is set on the edge in a recording area on each of theinner and outer-circumference sides of the recording medium 81 as shownin FIG. 15.

In the example shown in FIG. 15, the left side is theinner-circumference side of the recording medium 81 and the right sideis the outer-circumference side of the recording medium 81. Informationis recorded onto the recording medium 81 in the direction from theinner-circumference side to the outer-circumference side. In addition,the recording medium 81 includes a lead-in zone on the edge of theinner-circumference side and a lead-out zone on the edge of theouter-circumference side. The lead-in zone and the lead-out zone areeach an area not used for recording information or an area containing norecorded information.

In this case, in particular, the initialization section 62 a sets an ISA(inner spare area) as an area adjacent to the lead-in zone and an OSA(outer spare area) as an area adjacent to the lead-out zone. An areabetween the ISA and the OSA is used as a user area or a user data area.Virtually, various kinds of information are recorded in the user area.Information is thus recorded into the user area in the direction fromthe inner-circumference side to the outer-circumference side.Accordingly, increasing LSNs (logical Sector Numbers) are set in thedirection from the inner-circumference side to the outer-circumferenceside as shown by an arrow in the figure.

It is to be noted that the sizes of the ISA and the OSA can be setarbitrarily. By setting the sizes of the ISA and the OSA at largevalues, processing to record information into a damaged cluster asdescribed later can be stabilized. By setting the sizes of the ISA andthe OSA at large values, however, the size of a valid area usable forrecording information decreases.

Let us assume for example that the recording medium 81 is a double-layerBD-R. In this case, on each of the two layers, an ISA and an OSA are seton the edge in a recording area on each of the inner andouter-circumference sides of the recording medium 81 as shown in FIG.16.

In an example shown in FIG. 16, the left side is the inner-circumferenceside of the recording medium 81 and the right side is theouter-circumference side of the recording medium 81. An upper layer L0shown in the upper diagram of FIG. 16 is the first layer and a lowerupper layer L1 shown in the lower diagram of the figure is the secondlayer.

In the case of the 2-layer BD-R recording medium 81, information isrecorded onto the first layer of the recording medium 81 in thedirection from the inner-circumference side to the outer-circumferenceside and the second layer of the recording medium 81 in the directionfrom the outer-circumference side to the inner-circumference side. Thefirst layer of the recording medium 81 includes a lead-in zone 0 on theedge of the inner-circumference side and a lead-out zone 0 on the edgeof the outer-circumference side. As described above, the lead-in zone 0and the lead-out zone 0 are each an area not used for recordinginformation or an area containing no recorded information. On the otherhand, the second layer of the recording medium 81 includes a lead-outzone 1 on the edge of the inner-circumference side and a lead-in zone 1on the edge of the outer-circumference side. By the same token, thelead-in zone 1 and the lead-out zone 1 are each an area not used forrecording information or an area containing no recorded information.

In this case, the initialization section 62 a sets an ISA 0 (inner sparearea 0) as an area adjacent to the lead-in zone 0 and an OSA 0 (outerspare area 0) as an area adjacent to the lead-out zone 0 on the firstlayer. An area between the ISA 0 and the OSA 0 is used as a user area ora user data area. Virtually, various kinds of information are recordedin the user area. Information is thus recorded into the user area in thedirection from the inner-circumference side to the outer-circumferenceside. Accordingly, increasing LSNs (Logical Sector Numbers) are set inthe direction from the inner-circumference side to theouter-circumference side as shown by an arrow in the figure.

On the other hand, the initialization section 62 a sets an ISA 1 (innerspare area 1) as an area adjacent to the lead-out zone 1 and an OSA 1(outer spare area 1) as an area adjacent to the lead-in zone 1 on thesecond layer. An area between the ISA 0 and the OSA 0 is used as a userarea or a user data area. Virtually, various kinds of information arerecorded in the user area. Information is thus recorded into the userarea in the direction from the outer-circumference side to theinner-circumference side. Accordingly, increasing LSNs (Logical SectorNumbers) are set in the direction from the outer-circumference side tothe inner-circumference side as shown by an arrow in the figure.

It is to be noted that processing to set SA areas including TDMA areaswill be described in detail by referring to a flowchart shown in FIG.46.

Let us refer back to the flowchart shown in FIG. 14 and continue theexplanation of the processing to format the recording medium 81.

In a process carried out at a step S2, the initialization section 62 arequests the alternation-information management section 63 to generate aDL (Defect List). At this request, the alternation-informationmanagement section 63 generates a DL and stores the DL in the memory 63a. It is to be noted that, at this stage, the DL does not include anyinformation.

Then, in a process carried out at the next step S3, the initializationsection 62 a controls the write section 73 in order to drive therecording/reproduction block 53 to set a volume space on the recordingmedium 81. That is to say, as shown in the upper diagram of FIG. 18, forexample, a volume space is set. It is to be noted that FIG. 18 showsexamples for a case in which the recording medium 81 is a single-layerBD-R.

Subsequently, in a process carried out at the next step S4, theinitialization section 62 a controls the write section 73 in order todrive the recording/reproduction block 53 to set a volume structure areaused for storing information on the structure of the volume and ananchor area used for storing anchor information. In the upper diagram ofFIG. 18, the volume structure area is indicated by the words ‘VolumeStr.’ and the anchor area is indicated by the word ‘Anchor’. It is to benoted that, in the example shown in FIG. 18, the same file-systeminformation is stored at two locations. Thus, a volume structure areaand anchor area corresponding to the main FS area and a volume structurearea and anchor area corresponding to the mirror FS area are set. Thevolume structure area and anchor area corresponding to the main FS areaare a volume structure area indicated by the words ‘Volume Str.’ and ananchor area indicated by the word ‘Anchor’ in a block B111 shown in thefigure. On the other hand, the volume structure area and anchor areacorresponding to the mirror FS area are a volume structure areaindicated by the words ‘Volume Str.’ and an anchor area indicated by theword ‘Anchor’ in a block B113 shown in the figure.

Then, in a process carried out at the next step S5, the initializationsection 62 a controls the write section 73 in order to drive therecording/reproduction block 53 to set an FS area on the recordingmedium 81 as an area to be used for recording file-system information.That is to say, an area indicated by notation FS in the upper diagram ofFIG. 18 to be described later is set. It is to be noted that, in theexample shown in FIG. 18, the same file-system information is stored attwo locations. Thus, a main FS area and a mirror FS area are set. In thefigure, the main FS area is an area indicated by the words FS (Metadata)in the block B111. On the other hand, the mirror FS area is an areaindicated by the words FS (MD-Mirror) in the block B113.

It is to be noted that, in the example shown in FIG. 18, pieces ofinformation are laid out, each being recorded in an SRR. From the leftside, the pieces of information are inner-circumference-side informationon the structure of the volume, anchor information on theinner-circumference side, a main FS, files (Stream+DB), a mirror FS,outer-circumference-side information on the structure of the volume andanchor information on the outer-circumference side.

By carrying out the processed described above, an ISA, an OSA, a volumespace, anchor areas, areas each used for recording information on thestructure of the volume and FS areas are set on the recording medium 81.The ISA and the OSA are each an area used as alternate sectors. It is tobe noted that, in the formatting processing, only the areas describedabove are set. Virtually, no information is written into the set areas.The main FS indicated as the FS (Metadata) in the figure and the mirrorFS indicated as the FS (MD-Mirror) can be swapped with each other. Inaddition, it is also possible to set only one FS. In this case, the FScan be set on the inner-circumference side or the outer-circumferenceside.

Next, by referring to a flowchart shown in FIG. 17, the followingdescription explains processing to write information onto the recordingmedium 81, which has been formatted (or initialized) in a processcarried out by the recording/reproduction mechanism section 22 shown inFIG. 3 as represented by the flowchart shown in FIG. 14.

The flowchart shown in FIG. 17 begins with a step S11 at which thefile-system information generation section 62 generates file-systeminformation on the basis of information such as the attribute of a file,in which information is to be incrementally recorded, or a file to beupdated and fetches the generated file-system information.

Then, in a process carried out at the next step S12, the file-systeminformation generation section 62 produces a result of determination asto whether or not this write processing is being carried out for thefirst time.

If the determination result produced in the process carried out at thestep S12 indicates that this write processing is being carried out forthe first time, the flow of the processing goes on to a step S13 atwhich the file-system information generation section 62 drives therecording/reproduction block 53 to write files referred to as files(Stream+DB) in FIG. 18 into the user area on the recording medium 81.The written files are files supplied to the write section 73 from theECC encoding section 71 by way of the modulation section 72. The files(Stream+DB) are a file containing stream data and a file containing adatabase used for controlling the stream data.

To be more specific, as shown in the upper diagram of FIG. 18, thefile-system information generation section 62 drives therecording/reproduction block 53 to write the files (Stream+DB) shown inthe figure as files supplied to the write section 73 from the ECCencoding section 71 by way of the modulation section 72 into a blockB112 set on the recording medium 81 in the formatting processing. It isto be noted that, as described earlier, FIG. 18 shows a typical case inwhich the recording medium 81 is a single-layer BD-R.

Then, in a process carried out at the next step S14, the file-systeminformation generation section 62 drives the recording/reproductionblock 53 to write a main FS supplied to the write section 73 from theECC encoding section 71 by way of the modulation section 72 into theuser area set on the recording medium 81.

To be more specific, as shown in the upper diagram of FIG. 18, thefile-system information generation section 62 drives therecording/reproduction block 53 to write an FS (Metadata) shown in thefigure as file-system information supplied to the write section 73 fromthe ECC encoding section 71 by way of the modulation section 72 into ablock B111 set on the recording medium 81 in the formatting processingas an area used for recording a main FS.

Then, in a process carried out at the next step S15, the file-systeminformation generation section 62 drives the recording/reproductionblock 53 to write inner-circumference-side information on the structureof the volume and anchor information on the inner-circumference sideinto the user area set on the recording medium 81. Theinner-circumference-side information on the structure of the volume andanchor information on the inner-circumference side are pieces ofinformation supplied to the write section 73 from the ECC encodingsection 71 by way of the modulation section 72.

To be more specific, as shown in the upper diagram of FIG. 18, thefile-system information generation section 62 drives therecording/reproduction block 53 to write ‘Volume Str.’ and ‘Anchor’shown in the figure as respectively the inner-circumference-sideinformation on the structure of the volume and the anchor information onthe inner-circumference side into a block B111 set on the recordingmedium 81 in the formatting processing as an area used for recordinginner-circumference-side information on the structure of the volume andanchor information on the inner-circumference side. Theinner-circumference-side information on the structure of the volume andanchor information on the inner-circumference side are pieces ofinformation are supplied to the write section 73 from the ECC encodingsection 71 by way of the modulation section 72 as pieces of informationcorresponding to the main FS.

Then, in a process carried out at the next step S16, the file-systeminformation generation section 62 drives the recording/reproductionblock 53 to write a mirror FS supplied to the write section 73 from theECC encoding section 71 by way of the modulation section 72 into theuser area set on the recording medium 81.

To be more specific, as shown in the upper diagram of FIG. 18, thefile-system information generation section 62 drives therecording/reproduction block 53 to write an FS (MD-Mirror) shown in thefigure as file-system information supplied to the write section 73 fromthe ECC encoding section 71 by way of the modulation section 72 into ablock B113 set on the recording medium 81 in the formatting processingas an area used for recording a mirror FS.

Then, in a process carried out at the next step S17, the file-systeminformation generation section 62 drives the recording/reproductionblock 53 to write outer-circumference-side information on the structureof the volume and anchor information on the outer-circumference sideinto the user area set on the recording medium 81. Theouter-circumference-side information on the structure of the volume andthe anchor information on the outer-circumference side are pieces ofinformation supplied to the write section 73 from the ECC encodingsection 71 by way of the modulation section 72.

To be more specific, as shown in the upper diagram of FIG. 18, thefile-system information generation section 62 drives therecording/reproduction block 53 to write ‘Volume Str.’ and two ‘Anchor’sshown in the figure as respectively the outer-circumference-sideinformation on the structure of the volume and the anchor information onthe outer-circumference side into a block B113 set on the recordingmedium 81 in the formatting processing as an area used for recordingouter-circumference-side information on the structure of the volume andanchor information on the outer-circumference side. Theouter-circumference-side information on the structure of the volume andthe anchor information on the outer-circumference side are pieces ofinformation supplied to the write section 73 from the ECC encodingsection 71 by way of the modulation section 72 as pieces of informationcorresponding to the mirror FS.

If the determination result produced in the process carried out at thestep S12 indicates that this write processing was carried out at leastonce before at the steps S13 to S17, on the other hand, the flow of theprocessing goes on to a step S18.

In a process carried out at the step S18, the file-system informationgeneration section 62 drives the recording/reproduction block 53 towrite files referred to as files (Stream+DB) into the user area on therecording medium 81. The written files are files supplied to the writesection 73 from the ECC encoding section 71 by way of the modulationsection 72. The files (Stream+DB) are a file containing stream data anda file containing a database used for controlling the stream data.

To be more specific, as shown in the middle diagram of FIG. 18, thefile-system information generation section 62 drives therecording/reproduction block 53 to write the files (Stream+DB) shown inthe figure as files supplied to the write section 73 from the ECCencoding section 71 by way of the modulation section 72 into a blockB112′ set on the recording medium 81 in the formatting processing, forexample, if information has been recorded like in the processing stateshown in the upper diagram of FIG. 18. To put it in more detail, in aprocess to incrementally record information in an already existing file,the file-system information generation section 62 incrementally recordsnew additional information in the block B112′ shown in the middlediagram of FIG. 18, adding the new information to the informationalready recorded in the block B112 shown in the upper diagram of FIG.18. In a process to record a file containing new information as anupdate of the information already recorded in the block B112 shown inthe upper diagram of FIG. 18, on the other hand, the file alreadyrecorded in the block B112 is put in a state of being unreadable andinformation to be recorded into the block B112′ is constructed as anewly updated file to be recorded in the block B112′ adjacent to theblock B112.

Then, in a process carried out at the next step S19, the file-systeminformation generation section 62 controls the write section 73 throughthe ECC encoding section 71 and the modulation section 72 to put themain FS referred to as an FS (Metadata), the information on thestructure of the volume and the anchor information in a state of beingunreadable by the recording/reproduction block 53 out from the recordingmedium 81.

To be more specific, the file-system information generation section 62puts the main FS referred to as an FS (Metadata), the information on thestructure of the volume and the anchor information in a state of beingunreadable by the recording/reproduction block 53 out from the recordingmedium 81. The main FS referred to as an FS (Metadata), the informationon the structure of the volume and the anchor information are pieces ofinformation already recorded in the block B111 as shown in the middlediagram of FIG. 18. It is to be noted that, in the diagrams shown inFIG. 18, an area put in a state of being unreadable by therecording/reproduction block 53 out from the recording medium 81 isshown as a black box marked with white characters. An unreadable areamentioned in the following description is also shown in figures as sucha black box.

Then, in a process carried out at the next step S20, the file-systeminformation generation section 62 searches the recording area for aclosest SA area allowing new information to be recorded therein. The newinformation to be recorded into the closest SA area is a main FSreferred to as an FS (Metadata), information on the structure of thevolume and anchor information. The main FS referred to as an FS(Metadata), the information on the structure of the volume and theanchor information are pieces of information generated in a processcarried out at the step S19 to incrementally record information in analready existing file or update an already existing file.

To be more specific, in the case of a single-layer BR-D, an SA area isan area in either the OSA provided on the outer-circumference side ofthe disk or the ISA provided on the inner-circumference side of thedisk. In the example shown in the middle diagram of FIG. 18, forexample, the closest SA area found in the search process is an ISA area.Thus, the file-system information generation section 62 selects the areain the ISA to be used for recording the main FS referred to as an FS(Metadata), the information on the structure of the volume and theanchor information as shown in the middle diagram of FIG. 18.

Then, in a process carried out at the next step S21, the file-systeminformation generation section 62 supplies the main FS to the writesection 73 by way of the ECC encoding section 71 and the modulationsection 72 to be recorded by the recording/reproduction block 53 in anSA area found in the search process carried out at the step S20.

To be more specific, as shown in the middle diagram of FIG. 18, thefile-system information generation section 62 supplies the main FS tothe write section 73 by way of the ECC encoding section 71 and themodulation section 72 to be recorded in a block B111′ of an SA area onthe recording medium 81.

Then, in a process carried out at the next step S22, the file-systeminformation generation section 62 supplies the inner-circumference-sideinformation on the structure of the volume and the anchor information onthe inner-circumference side to the write section 73 by way of the ECCencoding section 71 and the modulation section 72 as pieces ofinformation corresponding to the main FS to be recorded by therecording/reproduction block 53 in an SA area found in the searchprocess carried out at the step S20.

To be more specific, the file-system information generation section 62supplies the inner-circumference-side information on the structure ofthe volume and the anchor information on the inner-circumference side tothe write section 73 by way of the ECC encoding section 71 and themodulation section 72 to be recorded in the block B111′ of an SA area onthe recording medium 81 as shown in the middle diagram of FIG. 18.

Then, in a process carried out at the next step S23, the file-systeminformation generation section 62 controls the write section 73 throughthe ECC encoding section 71 and the modulation section 72 to put theouter-circumference-side mirror FS referred to as an FS (MD-Mirror), theouter-circumference-side information on the structure of the volume andthe anchor information on the outer-circumference side in a state ofbeing unreadable by the recording/reproduction block 53 out from therecording medium 81.

To be more specific, the file-system information generation section 62puts the mirror FS referred to as an FS (MD-Mirror), the information onthe structure of the volume and the anchor information in a state ofbeing unreadable by the recording/reproduction block 53 out from therecording medium 81. The mirror FS referred to as an FS (MD-Mirror), theinformation on the structure of the volume and the anchor informationare pieces of information already recorded in the block B113 as shown inthe middle diagram of FIG. 18.

Then, in a process carried out at the next step S24, the file-systeminformation generation section 62 searches the recording area for aclosest SA area allowing new information to be recorded therein. The newinformation to be recorded into the closest SA area is a mirror FSreferred to as an FS (MD-Mirror), outer-circumference-side informationon the structure of the volume and anchor information on theouter-circumference side. The mirror FS referred to as an FS(MD-Mirror), outer-circumference-side information on the structure ofthe volume and anchor information on the outer-circumference side arepieces of information already generated in a process carried out at thestep S23.

To be more specific, in the case of a single-layer BR-D, an SA area isan area in either the OSA provided on the outer-circumference side ofthe disk or the ISA provided on the inner-circumference side of thedisk. In the example shown in the middle diagram of FIG. 18, forexample, the closest SA area found in the search process is an OSA area.Thus, the file-system information generation section 62 selects the areain the OSA as an area to be used for recording the mirror FS referred toas an FS (MD-Mirror), the outer-circumference-side information on thestructure of the volume and the anchor information on theouter-circumference side as shown in the middle diagram of FIG. 18.

Then, in a process carried out at the next step S25, the file-systeminformation generation section 62 supplies the mirror FS to the writesection 73 by way of the ECC encoding section 71 and the modulationsection 72 to be recorded by the recording/reproduction block 53 in anSA area found in the search process carried out at the step S24.

To be more specific, the file-system information generation section 62supplies the mirror FS to the write section 73 by way of the ECCencoding section 71 and the modulation section 72 to be recorded in ablock B113′ in the OSA on the recording medium 81 as shown in the middlediagram of FIG. 18.

Then, in a process carried out at the next step S26, the file-systeminformation generation section 62 supplies the outer-circumference-sideinformation on the structure of the volume and the anchor information onthe outer-circumference side to the write section 73 by way of the ECCencoding section 71 and the modulation section 72 to be recorded by therecording/reproduction block 53 in an SA area found in the searchprocess carried out at the step S24. The outer-circumference-sideinformation on the structure of the volume and the anchor information onthe outer-circumference side are pieces of information corresponding tothe mirror FS.

To be more specific, the file-system information generation section 62supplies the outer-circumference-side information on the structure ofthe volume and the anchor information on the outer-circumference side tothe write section 73 by way of the ECC encoding section 71 and themodulation section 72 to be recorded in the block B113′ in the OSA onthe recording medium 81 as shown in the middle diagram of FIG. 18.

In a process to add information to a file already recorded on therecording medium 81 as described above by referring to the middlediagram of FIG. 18 or update an already existing file shown in themiddle diagram of FIG. 18, on the other hand, at the step S18, as shownin the lower diagram of FIG. 18, the file-system information generationsection 62 drives the recording/reproduction block 53 to write the files(Stream+DB) shown in the figure as files supplied to the write section73 from the ECC encoding section 71 by way of the modulation section 72into the block B112″, which has been set on the recording medium 81 inthe formatting processing, as shown in the lower diagram of FIG. 18. Toput it in more detail, in a process to incrementally record informationin an already existing file, the file-system information generationsection 62 incrementally records new additional information in the blockB112″ shown in the lower diagram of FIG. 18, adding the new informationto the information already recorded in the block B112′ shown in themiddle diagram of FIG. 18. In a process to record a file containing newinformation as an update of the information already recorded in theblock B112′ shown in the middle diagram of FIG. 18, on the other hand,the file already recorded in the block B112′ is put in a state of beingunreadable and information to be recorded into the block B112″ isconstructed as a newly updated file to be recorded in the block B112″adjacent to the block B112′.

Then, in a process carried out at the next step S19, as shown in thelower diagram of FIG. 18, the file-system information generation section62 puts the main FS referred to as an FS (Metadata), the information onthe structure of the volume and the anchor information in a state ofbeing unreadable by the recording/reproduction block 53 out from therecording medium 81. The main FS referred to as an FS (Metadata), theinformation on the structure of the volume and the anchor informationare pieces of information already recorded in the block B111′.

Then, in a process carried out at the next step S20, in the case of theexample shown in the lower diagram of FIG. 18, for example, thefile-system information generation section 62 searches the recordingarea for a closest SA area allowing new information to be recordedtherein. The new information to be recorded into the closest SA area isa new main FS referred to as an FS (Metadata), new information on thestructure of the volume and new anchor information. If the closest SAarea is an area in the ISA, the file-system information generationsection 62 selects the area in the ISA as the closest SA area to be usedfor recording the new main FS referred to as an FS (Metadata), the newinformation on the structure of the volume and the new anchorinformation.

Then, in a process carried out at the next step S21, in the case of theexample shown in the lower diagram of FIG. 18, the file-systeminformation generation section 62 supplies the main FS to the writesection 73 by way of the ECC encoding section 71 and the modulationsection 72 to be recorded in a block B111″ of an ISA area on therecording medium 81.

Then, in a process carried out at the next step S22, in the case of theexample shown in the lower diagram of FIG. 18, the file-systeminformation generation section 62 supplies the information on thestructure of the volume and the anchor information to the write section73 by way of the ECC encoding section 71 and the modulation section 72to be recorded in the block B111″ of an ISA area on the recording medium81.

Then, in a process carried out at the next step S23, in the case of theexample shown in the lower diagram of FIG. 18, the file-systeminformation generation section 62 puts the mirror FS referred to as anFS (MD-Mirror), the information on the structure of the volume and theanchor information in a state of being unreadable by therecording/reproduction block 53 out from the recording medium 81 asshown in the lower diagram of FIG. 18. The mirror FS referred to as anFS (MD-Mirror), the information on the structure of the volume and theanchor information are pieces of information already recorded in theblock B113′ as shown in the middle diagram of FIG. 18.

Then, in a process carried out at the next step S24, in the case of theexample shown in the lower diagram of FIG. 18, the file-systeminformation generation section 62 searches the recording area for aclosest SA area allowing new information to be recorded therein. The newinformation to be recorded into the closest SA area is a mirror FSreferred to as an FS (MD-Mirror), information on the structure of thevolume and anchor information. If the closest SA area is an area in theOSA, the file-system information generation section 62 selects the areain the OSA as the closest SA area to be used for recording the newmirror main FS referred to as an FS (MD-Mirror), the new information onthe structure of the volume and the new anchor information.

Then, in a process carried out at the next step S25, in the case of theexample shown in the lower diagram of FIG. 18, the file-systeminformation generation section 62 supplies the mirror FS to the writesection 73 by way of the ECC encoding section 71 and the modulationsection 72 to be recorded in a block B113″ in the OSA on the recordingmedium 81.

Then, in a process carried out at the next step S26, in the case of theexample shown in the lower diagram of FIG. 18, the file-systeminformation generation section 62 supplies the information on thestructure of the volume and the anchor information to the write section73 by way of the ECC encoding section 71 and the modulation section 72to be recorded in the block B113″ in the OSA on the recording medium 81.

In a process to add information to a file already recorded on therecording medium 81 or update the file, updates of the file-systeminformation, the anchor information and the information on the structureof the volume are sequentially recorded into alternate sectors of an SAarea instead of original sectors. Thus, a process to record a file ontothe recording medium 81 can be carried out without changing the logicaladdresses of the file-system information, the anchor information and theinformation on the structure of the volume in spite of the fact that thefile-system information, the anchor information and the information onthe structure of the volume are sequentially recorded at the alternatesectors physically different from the original sectors. Thus, it is nolonger necessary to change the logical addresses of information such asthe file-system information, the anchor information and the informationon the structure of the volume in every process to add information to afile already recorded on the recording medium 81 or update the file. Asa result, even for a recording medium allowing no overwriting of data onthe same location as is the case with a write-once recording medium,information that must be recorded at a fixed location in thelogical-address space appears like information treatable in a way as ifoverwriting were permitted.

It is to be noted that the information-recording processes carried outat the steps S13 to S18 as well as the steps S21, S22, S25 and S26 ofthe flowchart shown in FIG. 17 will be described in more detail later.

The example described above is a typical case in which the file-systeminformation is recorded by sequentially writing new updates of theinformation. For example, it is also possible to provide a configurationin which only a difference between file-system information beforeupdating and file-system information after the updating is recorded intoan SA area. An example of such a difference is information in a changeddirectory. In such a case, the post-updating file-system information onthe recording medium 81 can be generated from the file-systeminformation before the updating and the difference. As a result, theamount of information recorded in an SA area can be reduced.

In addition, in the processes carried out at the steps S20 and S24, therecording area is searched for a closest SA area allowing file-systeminformation, anchor information and information on the structure of thevolume to be recorded therein. In actuality, an SA area closest to thepresent location on the recording medium 81 is known in advance to acertain degree. Thus, pieces information on closest areas can becollected in a table or the like and, such a table can be generated inthe formatting process so that the table can be used in a process tofind out a closest SA area. By using such a table or the like, theprocess to search the recording area for a closest SA area can becompleted in a shorter period of time.

In addition, the above description exemplifies a case in which therecording medium 81 is a single-layer BD-R. However, even if therecording medium 81 is a double-layer BD-R, for example, file-systeminformation, anchor information and information on the structure of thevolume can be recorded. In a process to search the recording area for aclosest SA area, the closest SA area can be an area on the other layeras long as the distance to the closest SA area is physically shortest.That is to say, if file-system information, anchor information as wellas information on the structure of the volume can be recorded and theclosest SA area on the second layer is found physically closer than theclosest SA area on the first layer in a process to search the recordingarea for a closest SA area, the closest SA area on the second layer isselected. By selecting the closest SA area in this way, the updatedfile-system information, the updated anchor information as well as theupdated information on the structure of the volume can be read out fastfrom the closest area.

On top of that, the above description exemplifies a case in which a mainFS and its mirror FS are both recorded in an SA area. In this case, amain FS and its mirror FS are both recorded in an SA area every time newinformation is incrementally recorded in an already existing file or analready existing file is updated. It is thus necessary to allocate anarea in the ISA or the OSA as an area used for recording the main FS andits mirror FS so that, in consequence, it is feared that the size of theuser area on the recording medium 81 is limited to a small value.

In order to solve the above problem, only the main FS or its mirror FScan be recorded in an SA area.

FIG. 19 is a diagram showing the configuration of therecording/reproduction mechanism section 22 in which only a mirror FSand inner-circumference-side file-system information, anchor informationon the inner-circumference side as well as inner-circumference-sidestructure-volume information, which correspond to the mirror FS, arewritten into an SA area. It is to be noted that every component includedin the recording/reproduction mechanism section 22 shown in FIG. 19 as acomponent identical with its counterpart employed in therecording/reproduction mechanism section 22 shown in FIG. 3 is denotedby the same reference numeral as the counterpart and the explanation ofthe component is properly omitted.

The configuration of the recording/reproduction mechanism section 22shown in FIG. 19 is different from the configuration of therecording/reproduction mechanism section 22 shown in FIG. 3 in that therecording/reproduction mechanism section 22 shown in FIG. 19 employs acontrol section 301 as a substitute for the control section 51 employedin the recording/reproduction mechanism section 22 shown in FIG. 3. Thecontrol section 301 is different from the control section 51 in that thecontrol section 301 employs a file-system information recognitionsection 311 as a substitute for the file-system information recognitionsection 61 employed in the control section 51, a file-system informationgeneration section 312 as a substitute for the file-system informationgeneration section 62 employed in the control section 51, analternation-information management section 313 as substitute for thealternation-information management section 63 employed in the controlsection 51 and an alternation-information generation section 314 as asubstitute for the alternation-information generation section 64employed in the control section 51.

Basic functions of the file-system information recognition section 311are the same as those of the file-system information recognition section61 except that, in a process to recognize file-system information, thefile-system information recognition section 311 reads out a mirror FS,inner-circumference-side information on the structure of the volume aswell as anchor information on the inner-circumference side always fromfixed logical addresses and a main FS, outer-circumference-sideinformation on the structure of the volume as well as anchor informationon the outer-circumference side from the user area.

Basic functions of the file-system information generation section 312are the same as those of the file-system information generation section62 except that, in a process to incrementally record information in analready existing file or update an already existing file, thefile-system information generation section 312 records a main FS,outer-circumference-side information on the structure of the volume sideas well as anchor information on the outer-circumference side into theuser area and a mirror FS, inner-circumference-side information on thestructure of the volume as well as anchor information on theinner-circumference side into an SA area.

Basic functions of an initialization section 312 a employed in thefile-system information generation section 312 are the same as those ofthe initialization section 62 a employed in the file-system informationgeneration section 62 except that, in the formatting process, theinitialization section 312 a swaps the locations of the mirror FS andthe main FS with each other as well as the locations of the informationon the inner side and the information on the outer side with each other.To be more specific, as shown in the upper diagram of FIG. 21 to bedescribed later, the anchor information and information on the structureof the volume corresponding to the mirror FS is set in a block B131whereas the anchor information and information on the structure of thevolume corresponding to the main FS is set in a block B133. It is to benoted that, in the example shown in FIG. 21, theinner-circumference-side information on the structure of the volume, theanchor information on the inner-circumference side, the main FS, a file,the mirror FS, the outer-circumference-side information on the structureof the volume and the anchor information on the outer-circumference sideare each set in an SRR.

As described above, in a process to incrementally record information inan already existing file or update an already existing file in thisexample, only the mirror FS, the inner-circumference-side information onthe structure of the volume and the anchor information on theinner-circumference side are recorded in an SA area, but the main FS,the outer-circumference-side information on the structure of the volumeand the anchor information on the outer-circumference side are recordedin the user area. It is to be noted, however, that the mirror FS, theinner-circumference-side information on the structure of the volume andthe anchor information on the inner-circumference side can also berecorded in the user area, while the main FS, theouter-circumference-side information on the structure of the volume andthe anchor information on the outer-circumference side are recorded inan SA area.

It is also worth noting that the alternation-information managementsection 313, a memory 313 a, the alternation-information generationsection 314 and a memory 314 a are identical respectively with thealternation-information management section 63, the memory 63 a, thealternation-information generation section 64 and the memory 64 a, whichare employed in the recording/reproduction apparatus 22 shown in FIG. 3so that explanations of the alternation-information management section313, the memory 313 a, the alternation-information generation section314 and the memory 314 a are omitted.

Next, write processing carried out by the recording/reproductionmechanism section 22 shown in FIG. 19 is explained by referring to aflowchart shown in FIG. 20.

It is to be noted that since processes carried out at steps S41 to S49and steps S52 to S55 of the flowchart shown in FIG. 20 are identicalrespectively with those carried out at the steps S11 to S19 and thesteps S23 to S26 of the flowchart shown in FIG. 17, the processes arenot explained in detail.

In a process carried out at the step S41, the file-system informationgeneration section 312 generates file-system information. Then, in aprocess carried out at the next step S42, the file-system informationgeneration section 312 produces a result of determination as to whetheror not this write processing is being carried out for the first time. Ifthe determination result produced in the process carried out at the stepS42 indicates that this write processing is being carried out for thefirst time, the flow of the processing goes on to a step S43 at whichthe file-system information generation section 312 drives therecording/reproduction block 53 to write files (Stream+DB) shown in FIG.21 into a block B132 set in the user area as shown in the upper diagramof the figure.

Then, in a process carried out at the next step S44, the file-systeminformation generation section 312 drives the recording/reproductionblock 53 to write an FS (Metadata) shown in FIG. 21 as a main FS into ablock B133 set in the user area as shown in the upper diagram of thefigure.

Subsequently, in a process carried out at the next step S45, thefile-system information generation section 312 drives therecording/reproduction block 53 to write ‘Volume Str.’ and ‘Anchor’shown in FIG. 21 into the block B133 set in the user area asrespectively outer-circumference-side information on the structure ofthe volume and anchor information on the outer-circumference side asshown in the upper diagram of the figure. The outer-circumference-sideinformation on the structure of the volume and the anchor information onthe outer-circumference side are pieces of information corresponding tothe main FS.

Then, in a process carried out at the next step S46, the file-systeminformation generation section 312 drives the recording/reproductionblock 53 to write an FS (MD-Mirror) shown in FIG. 21 as a mirror FS intoa block B131 set in the user area as shown in the upper diagram of thefigure.

Subsequently, in a process carried out at the next step S47, thefile-system information generation section 312 drives therecording/reproduction block 53 to write ‘Volume Str.’ and ‘Anchor’shown in FIG. 21 as respectively inner-circumference-side information onthe structure of the volume and anchor information on theinner-circumference side into the block B131 set in the user area asshown in the upper diagram of the figure. The inner-circumference-sideinformation on the structure of the volume and the anchor information onthe inner-circumference side are pieces of information corresponding tothe mirror FS.

If the determination result produced in the process carried out at thestep S42 indicates that this write processing has been carried outbefore, that is, files have been recorded before at the steps S43 to S47and then information is to be added to the files or the files are to beupdated this time, on the other hand, the flow of the processing goes onto a step S48 at which the file-system information generation section312 drives the recording/reproduction block 53 to incrementally recordinformation referred to as files (Stream+DB) shown in FIG. 21 into ablock B132′ set in the user area as shown in the middle diagram of thefigure.

Then, in a process carried out at the next step S49, the file-systeminformation generation section 312 puts the main FS, theouter-circumference-side information on the structure of the volume andthe anchor information on the outer-circumference side in a state ofbeing unreadable as shown in the middle diagram of the figure. Theouter-circumference-side information on the structure of the volume andthe anchor information on the outer-circumference side are pieces ofinformation already recorded in the immediately preceding writeprocessing.

Then, in a process carried out at the next step S50, the file-systeminformation generation section 312 supplies the main FS to the writesection 73 by way of the ECC encoding section 71 and the modulationsection 72 to be recorded by the recording/reproduction block 53 in ablock B133′ of the user area as shown in the middle diagram of FIG. 21.

Then, in a process carried out at the next step S51, the file-systeminformation generation section 312 supplies the outer-circumference-sideinformation on the structure of the volume and the anchor information onthe outer-circumference side to the write section 73 by way of the ECCencoding section 71 and the modulation section 72 to be recorded by therecording/reproduction block 53 in the block B133′ as shown in themiddle diagram of FIG. 21. The outer-circumference-side information onthe structure of the volume and the anchor information on theouter-circumference side are pieces of information corresponding to themain FS.

Subsequently, in a process carried out at the next step S52, thefile-system information generation section 312 puts the mirror FSreferred to as an FS (MD-Mirror), the inner-circumference-sideinformation on the structure of the volume and the anchor information onthe inner-circumference side in a state of being unreadable. The mirrorFS, the information on the structure of the volume and the anchorinformation have been recorded in a block B131 as shown in the middlediagram of FIG. 21.

Then, in a process carried out at the next step S53, the file-systeminformation generation section 312 searches the recording area for aclosest SA area allowing new information to be recorded therein. The newinformation to be recorded into the closest SA area is a mirror FSreferred to as an FS (MD-Mirror), inner-circumference-side informationon the structure of the volume and anchor information on theinner-circumference side. The closest SA area being searched for is thearea closest to the block B131 at which the mirror FS, theinner-circumference-side information on the structure of the volume andthe anchor information on the inner-circumference side have beenrecorded. In the example shown in the middle diagram of FIG. 21, theclosest SA area found in the search process is an ISA area.

Then, in a process carried out at the next steps S54 and S55, thefile-system information generation section 312 supplies the mirror FS aswell as the inner-circumference-side information on the structure of thevolume and the anchor information on the inner-circumference side to thewrite section 73 to be recorded by the recording/reproduction block 53in a block B131′, which has been found in the search process as an areain the ISA, as shown in the middle diagram of FIG. 21. Theinner-circumference-side information on the structure of the volume andthe anchor information on the inner-circumference side are pieces ofinformation corresponding to the mirror FS.

If information is further incrementally recorded into an alreadyexisting file in the state shown in the middle diagram of FIG. 21 or thefile is updated, at the step S48, as shown in the lower diagram of FIG.21, the file-system information generation section 312 drives therecording/reproduction block 53 to incrementally record informationreferred to as the files (Stream+DB) shown in the figure into a blockB132″ in the user area as shown in the lower diagram of FIG. 21.

Then, in a process carried out at the next step S49, the file-systeminformation generation section 312 puts the main FS, theouter-circumference-side information on the structure of the volume andthe anchor information on the outer-circumference side in a state ofbeing unreadable as shown in the lower diagram of FIG. 21. The main FS,the outer-circumference-side information on the structure of the volumeand the anchor information on the outer-circumference side are pieces ofinformation already recorded in a block B133′ in the immediatelypreceding write processing.

Then, in a process carried out at the next step S50, the file-systeminformation generation section 312 supplies the main FS to the writesection 73 by way of the ECC encoding section 71 and the modulationsection 72 to be recorded by the recording/reproduction block 53 in ablock B133″ of the user area as shown in the lower diagram of FIG. 21.

Subsequently, in a process carried out at the next step S51, thefile-system information generation section 312 supplies theouter-circumference-side information on the structure of the volume andthe anchor information on the outer-circumference side to the writesection 73 by way of the ECC encoding section 71 and the modulationsection 72 to be recorded by the recording/reproduction block 53 in theblock B133″ of the user area as shown in the lower diagram of FIG. 21.The outer-circumference-side information on the structure of the volumeand the anchor information on the outer-circumference side are pieces ofinformation corresponding to the main FS.

Then, in a process carried out at the next step S52, the file-systeminformation generation section 312 puts the mirror FS referred to as anFS (MD-Mirror), the inner-circumference-side information on thestructure of the volume and the anchor information on theinner-circumference side in a state of being unreadable as shown in thelower diagram of FIG. 21. The inner-circumference-side information onthe structure of the volume and the anchor information on theinner-circumference side have been recorded in the block B131′.

Subsequently, in a process carried out at the next step S53, thefile-system information generation section 312 searches the recordingarea for a closest SA area allowing new information to be recordedtherein. The new information to be recorded into the closest SA area isa mirror FS referred to as an FS (MD-Mirror), inner-circumference-sideinformation on the structure of the volume and anchor information on theinner-circumference side. The closest SA area being searched for is thearea closest to the block B131′ at which the mirror FS, theinner-circumference-side information on the structure of the volume andthe anchor information on the inner-circumference side have beenrecorded. In the example shown in the lower diagram of FIG. 21, theclosest SA area found in the search process is an ISA area.

Then, in a process carried out at the next steps S54 and S55, thefile-system information generation section 312 supplies the mirror FS aswell as the inner-circumference-side information on the structure of thevolume and the anchor information on the inner-circumference side to thewrite section 73 to be recorded by the recording/reproduction block 53in a block B131″, which has been found in the search process as an areain the SA area, as shown in the lower diagram of FIG. 21. Theinner-circumference-side information on the structure of the volume andthe anchor information on the inner-circumference side are pieces ofinformation corresponding to the mirror FS.

As described above, in a process to add information to a file alreadyrecorded on the recording medium 81 or update the file, only the mirrorFS is recorded to an SA area in addition to the inner-circumference-sideinformation on the structure of the volume and the anchor information onthe inner-circumference side. The inner-circumference-side informationon the structure of the volume and the anchor information on theinner-circumference side are pieces of information corresponding to themirror FS. Thus, in comparison with the recording/reproduction mechanismsection 22 shown in FIG. 3, the size of the consumed SA area can bereduced to about half the original size. In this case, however, therecording locations of the main FS as well as the information on thestructure of the volume and the anchor information are changed, makingit necessary to alter their logical addresses. The information on thestructure of the volume and the anchor information are pieces ofinformation corresponding to the main FS. In the case of theconfiguration shown in FIG. 21, for example, the recording locations arechanged from the block B133 to the block B133′ and finally to the blockB133″. In order to solve this problem, usually, only the mirror FSrecorded at a fixed logical address is read out to acquire the mirror FSfrom the recording medium 81. The main FS is read out from the user areaonly if the mirror FS cannot be read out from the recording medium 81 byall means for some reasons. In this way, this configuration offers botha merit of reading out file-system information from a fixed logicaladdress and a merit of having the same FS recorded at two differentlocations in addition to the efficient utilization of an SA area.

It is to be noted that the information-recording processes carried outat the steps S43 to S48 as well as the steps S48, S50, S51, S54 and S55of the flowchart shown in FIG. 20 will be described in more detaillater.

The above descriptions have explained typical FS double recording inwhich the same FS is recorded at two different locations as a main FSand a mirror FS respectively. In a process to add information to a filealready recorded on the recording medium 81 or update the file, however,only the main FS is recorded in the user area as file-systeminformation. Since only the inner-circumference-side information on thestructure of the volume and the anchor information on theinner-circumference side are recorded in an SA area, the size of therequired SA area can be reduced.

FIG. 22 is a diagram showing the configuration of therecording/reproduction mechanism section 22 in which only a main FS isrecorded in the user area and only anchor information on theinner-circumference side as well as inner-circumference-side informationon the structure of the volume are written into an SA area during aprocess to incrementally record information in an already existing fileor update an already existing file. It is to be noted that everycomponent included in the recording/reproduction mechanism section 22shown in FIG. 22 as a component identical with its counterpart employedin the recording/reproduction mechanism section 22 shown in FIG. 19 isdenoted by the same reference numeral as the counterpart and theexplanation of the component is properly omitted.

The configuration of the recording/reproduction mechanism section 22shown in FIG. 22 is different from the configuration of therecording/reproduction mechanism section 22 shown in FIG. 19 in that therecording/reproduction mechanism section 22 shown in FIG. 22 employs acontrol section 331 as a substitute for the control section 301 employedin the recording/reproduction mechanism section 22 shown in FIG. 19. Thecontrol section 331 is different from the control section 301 in thatthe control section 331 employs a file-system information recognitionsection 341 as a substitute for the file-system information recognitionsection 311 employed in the control section 301, a file-systeminformation generation section 342 as a substitute for the file-systeminformation generation section 312 employed in the control section 301,an alternation-information management section 343 as substitute for thealternation-information management section 313 employed in the controlsection 301 and an alternation-information generation section 344 as asubstitute for the alternation-information generation section 314employed in the control section 301.

Basic functions of the file-system information recognition section 341are the same as those of the file-system information recognition section311 except that, in a process to recognize file-system information, thefile-system information recognition section 341 reads out a main FS,outer-circumference-side information on the structure of the volume aswell as anchor information on the outer-circumference side. It is to benoted that in the typical configuration shown in FIG. 22, only astandalone main FS is recorded. Thus, the file-system informationrecognition section 341 reads out only a main FS as file-systeminformation.

Basic functions of the file-system information generation section 342are the same as those of the file-system information generation section312 except that, in a process to incrementally record information in analready existing file or update an already existing file, thefile-system information generation section 342 records standalonefile-system information, outer-circumference-side information on thestructure of the volume as well as anchor information on theouter-circumference side into the user area and inner-circumference-sideinformation on the structure of the volume as well as anchor informationon the inner-circumference side into an SA area.

Basic functions of an initialization section 342 a employed in thefile-system information generation section 342 are the same as those ofthe initialization section 312 a employed in the file-system informationgeneration section 312 except that, unlike the initialization section312 a, the initialization section 342 a sets a standalone main FS in theuser area. To be more specific, as shown in the upper diagram of FIG. 24to be described later, the standalone main FS, anchor information on theouter-circumference side and outer-circumference-side information on thestructure of the volume are set in a block B153 whereas anchorinformation on the inner-circumference side and inner-circumference-sideinformation on the structure of the volume are set in a block B151. Itis to be noted that, in the example shown in FIG. 24, theinner-circumference-side information on the structure of the volume, theanchor information on the inner-circumference side, the main FS, files,the mirror FS, the information on the structure of the volume and theanchor information are each set in an SRR.

It is to be noted that the alternation-information management section343, a memory 343 a, the alternation-information generation section 344and a memory 344 a are identical respectively with thealternation-information management section 63, the memory 63 a, thealternation-information generation section 64 and the memory 64 a, whichare employed in the recording/reproduction apparatus 22 shown in FIG. 3,so that explanations of the alternation-information management section343, the memory 343 a, the alternation-information generation section344 and the memory 344 a are omitted.

Next, write processing carried out by the recording/reproductionmechanism section 22 shown in FIG. 22 is explained by referring to aflowchart shown in FIG. 23.

It is to be noted that, since processes carried out at steps S71 to S81of the flowchart shown in FIG. 23 are identical with the processescarried out at the steps S41 to S45 and S47 to S51 of the flowchartshown in FIG. 20, the processes carried out at steps S71 to S81 are notexplained in detail.

In a process carried out at the step S71, file-system information isread in. Then, in a process carried out at the next step S72, thefile-system information generation section 342 produces a result ofdetermination as to whether or not this write processing is beingcarried out for the first time. If the determination result produced inthe process carried out at the step S72 indicates that this writeprocessing is being carried out for the first time, the flow of theprocessing goes on to a step S73 at which the file-system informationgeneration section 342 drives the recording/reproduction block 53 towrite files (Stream+DB) shown in FIG. 24 into a block B152 set in theuser area as shown in the upper diagram of the figure.

Then, in a process carried out at the next step S74, the file-systeminformation generation section 342 drives the recording/reproductionblock 53 to write an FS (Metadata) shown in FIG. 24 as a standalone mainFS into a block B153 set in the user area as shown in the upper diagramof the figure.

Subsequently, in a process carried out at the next step S75, thefile-system information generation section 342 drives therecording/reproduction block 53 to write ‘Volume Str.’ and ‘Anchor’shown in FIG. 24 into the block B153 as respectivelyouter-circumference-side information on the structure of the volume andanchor information on the outer-circumference side as shown in the upperdiagram of the figure.

Then, in a process carried out at the next step S76, the file-systeminformation generation section 342 drives the recording/reproductionblock 53 to write ‘Volume Str.’ and ‘Anchor’ shown in FIG. 24 into ablock B151 of the user area as respectively inner-circumference-sideinformation on the structure of the volume and anchor information on theinner-circumference side as shown in the upper diagram of the figure.

If the determination result produced in the process carried out at thestep S72 indicates that this write processing has been carried outbefore, that is, files have been recorded before at the steps S73 to S76and then information is to be added to the files or the files are to beupdated this time, on the other hand, the flow of the processing goes onto a step S77 at which the file-system information generation section342 drives the recording/reproduction block 53 to incrementally recordinformation in files (Stream+DB) shown in the FIG. 24 into a block B152′set the user area as shown in the middle diagram of the figure.

Then, in a process carried out at the next step S78, the file-systeminformation generation section 342 puts the main FS, theouter-circumference-side information on the structure of the volume andthe anchor information on the outer-circumference side in a state ofbeing unreadable. The main FS, the outer-circumference-side informationon the structure of the volume and the anchor information on theouter-circumference side are pieces of information already recorded inthe block B153 in the immediately preceding write processing.

Then, in a process carried out at the next step S79, as shown in themiddle diagram of FIG. 24, the file-system information generationsection 342 supplies the main FS to the write section 73 to be recordedin a block B153′ of the user area as file-system information.

Subsequently, in a process carried out at the next step S80, thefile-system information generation section 342 supplies theouter-circumference-side information on the structure of the volume andthe anchor information on the outer-circumference side to the writesection 73 to be recorded by the recording/reproduction block 53 in theblock B153′ of the user area as shown in the middle diagram of FIG. 24.

Then, in a process carried out at the next step S81, the file-systeminformation generation section 342 puts the inner-circumference-sideinformation on the structure of the volume and the anchor information onthe inner-circumference side in a state of being unreadable. Theinner-circumference-side information on the structure of the volume andthe anchor information on the inner-circumference side are pieces ofinformation already recorded in the block B151 shown in the middlediagram of FIG. 24.

Subsequently, in a process carried out at the next step S82, thefile-system information generation section 342 searches the recordingarea for a closest SA area allowing new information to be recordedtherein. The new information to be recorded into the closest SA area isinner-circumference-side information on the structure of the volume andanchor information on the inner-circumference side. The closest SA areabeing searched for is an area closest to the block B151 at which theinner-circumference-side information on the structure of the volume andthe anchor information on the inner-circumference side have beenrecorded. In the example shown in the middle diagram of FIG. 24, theclosest SA area found in the search process is an ISA area.

Then, in a process carried out at the next step S83, the file-systeminformation generation section 342 supplies the inner-circumference-sideinformation on the structure of the volume and the anchor information onthe inner-circumference side to the write section 73 to be recorded bythe recording/reproduction block 53 in a block B151′ of the ISA areafound in the search process as shown in the middle diagram of FIG. 24.

If information is further incrementally recorded into an alreadyexisting file in the state shown in the middle diagram of FIG. 24 or thefile is updated, at the step S77, as shown in the lower diagram of FIG.24, the file-system information generation section 342 drives therecording/reproduction block 53 to incrementally record informationreferred to as the files (Stream+DB) shown in the figure into a blockB152″ of the user area.

Then, in a process carried out at the next step S78, the file-systeminformation generation section 342 puts the main FS, the information onthe structure of the volume and the anchor information in a state ofbeing unreadable as shown in the lower diagram of FIG. 24. The main FS,the information on the structure of the volume and the anchorinformation have been recorded in the block B153′.

Then, in a process carried out at the next step S79, the file-systeminformation generation section 342 supplies the main FS to the writesection 73 to be recorded by the recording/reproduction block 53 in ablock B153″ of the user area as shown in the lower diagram of FIG. 24.

Subsequently, in a process carried out at the next step S80, thefile-system information generation section 342 supplies theouter-circumference-side information on the structure of the volume andthe anchor information on the outer-circumference side to the writesection 73 to be recorded by the recording/reproduction block 53 in theblock B153″ of the user area as shown in the lower diagram of FIG. 24.

Then, in a process carried out at the next step S81, the file-systeminformation generation section 342 puts the inner-circumference-sideinformation on the structure of the volume and the anchor information onthe inner-circumference side in a state of being unreadable. Theinner-circumference-side information on the structure of the volume andthe anchor information on the inner-circumference side have beenrecorded in a block B151′ as shown in the lower diagram of FIG. 24.

Subsequently, in a process carried out at the next step S82, thefile-system information generation section 342 searches the recordingarea for a closest SA area allowing new information to be recordedtherein. The new information to be recorded into the closest SA area isthe information on the structure of the volume and anchor information.The closest SA area being searched for is the area closest to the blockB151′ at which the information on the structure of the volume and theanchor information have been recorded. In the example shown in the lowerdiagram of FIG. 24, the closest SA area found in the search process isan ISA area.

Then, in a process carried out at the next step S83, the file-systeminformation generation section 342 supplies the inner-circumference-sideinformation on the structure of the volume and the anchor information onthe inner-circumference side to the write section 73 to be recorded bythe recording/reproduction block 53 in a block B151″ of the ISA areafound in the search process as shown in the lower diagram of FIG. 24.

As described above, in a process to add information to a file alreadyrecorded on the recording medium 81 or update the already recorded file,only the inner-circumference-side information on the structure of thevolume and the anchor information on the inner-circumference side arerecorded in the SA. Thus, the information on the structure of the volumeand the anchor information can be read out by specifying fixed logicaladdresses. In addition, in comparison with the recording/reproductionapparatus 22 shown in FIG. 3 or FIG. 19, the size of the consumed SAarea is small. Even in the configuration described above, however, therecording locations of the main FS, the outer-circumference-sideinformation on the structure of the volume and the anchor information onthe outer-circumference side are changed to, for example, the blocksB153, B153′ and B153″ shown in FIG. 24 so that it is necessary to modifytheir logical addresses.

It is to be noted that the information-recording processes carried outat the steps S73 to S77 as well the steps S79, S80 and S83 of theflowchart shown in FIG. 23 will be described in more detail later.

The above description explains a typical case in which file-systeminformation, information on the structure of the volume and anchorinformation or only information on the structure of the volume andanchor information are set at the beginning of the volume space and, inevery updating process, they are recorded in an SA area. In this case,the file-system information is both a main FS and a mirror FS or only amain FS. It is to be noted, however, that the information set andrecorded is not limited to this combination. For example, theinformation set and recorded can be only file-system information andinformation on the structure of the volume or anchor information.

In addition, the above description also explains a typical case in whichonly one of file-system information, information on the structure of thevolume and anchor information, which have been set at the beginning ofthe volume space, is recorded in an SA area so that, by updating therecorded file-system information, the information on the structure ofthe volume or the anchor information in a process to incrementallyrecord information in an already existing file or update the alreadyexisting file, it is possible to read out the file-system information,the information on the structure of the volume or the anchor informationwithout the need to change its logical address. However, in a process toincrementally record information in an already existing file or updatethe already existing file, a portion of the file can also be recorded inan SA area.

FIG. 25 is a diagram showing the configuration of arecording/reproduction apparatus 22 in which, during a process toincrementally record information in an already existing file or updatethe already existing file, a portion of the file is recorded in an SAarea in addition to file-system information, information on thestructure of the volume or anchor information.

It is to be noted that every component included in therecording/reproduction mechanism section 22 shown in FIG. 25 as acomponent identical with its counterpart employed in therecording/reproduction mechanism section 22 shown in FIG. 3 is denotedby the same reference numeral as the counterpart and the explanation ofthe component is properly omitted.

The configuration of the recording/reproduction mechanism section 22shown in FIG. 25 is different from the configuration of therecording/reproduction mechanism section 22 shown in FIG. 3 in that therecording/reproduction mechanism section 22 shown in FIG. 25 employs acontrol section 351 as a substitute for the control section 51 employedin the recording/reproduction mechanism section 22 shown in FIG. 3. Thecontrol section 351 is different from the control section 51 in that thecontrol section 351 employs a file-system information recognitionsection 361 as a substitute for the file-system information recognitionsection 61 employed in the control section 51, a file-system informationgeneration section 362 as a substitute for the file-system informationgeneration section 62 employed in the control section 51, analternation-information management section 363 as substitute for thealternation-information management section 63 employed in the controlsection 51 and an alternation-information generation section 364 as asubstitute for the alternation-information generation section 64employed in the control section 51.

Basic functions of the file-system information recognition section 361are the same as those of the file-system information recognition section61 except that, in a process to recognize file-system information, thefile-system information recognition section 361 reads out file-systeminformation, information on the structure of the volume, anchorinformation and a file always through fixed logical addresses from theISA on the inner-circumference side but reads outouter-circumference-side file-system information,outer-circumference-side information on the structure of the volume andanchor information on the outer-circumference side from the user area.Referred to hereafter as files (DB), files read out from the ISA are thedatabase (DB) of stream data.

Basic functions of the file-system information generation section 362are the same as those of the file-system information generation section62 except that, in a process to incrementally record information in analready existing file or update an already existing file, thefile-system information generation section 362 records file-systeminformation on the inner-circumference side, inner-circumference-sideinformation on the structure of the volume, anchor information on theinner-circumference side as well as files (DB) into an SA area andfile-system information on the outer-circumference side,outer-circumference-side information on the structure of the volume aswell as anchor information on the outer-circumference side into the userarea.

Basic functions of an initialization section 362 a employed in thefile-system information generation section 362 are the same as those ofthe initialization section 62 a employed in the file-system informationgeneration section 62 except that the initialization section 362 a setsfiles separately as stream data referred to as files (Stream) anddatabases referred to as files (DB). To be more specific, as shown inthe upper diagram of FIG. 27 to be described later, database informationreferred to as files (DB) is set in a block B171 in addition to anchorinformation and volume-structure information, which correspond to a mainFS referred to as an FS (Metadata). On the other hand, anchorinformation and information on the structure of the volume, whichcorrespond to a mirror FS referred to as an FS (MD-Mirror), are set in ablock B173.

It is to be noted that the alternation-information management section363, a memory 363 a, the alternation-information generation section 364and a memory 364 a are identical respectively with thealternation-information management section 63, the memory 63 a, thealternation-information generation section 64 and the memory 64 a, whichare employed in the recording/reproduction apparatus 22 shown in FIG. 3,so that explanations of the alternation-information management section363, the memory 363 a, the alternation-information generation section364 and the memory 364 a are omitted.

Next, write processing carried out by the recording/reproductionmechanism section 22 shown in FIG. 25 is explained by referring to aflowchart shown in FIG. 26.

It is to be noted that, since processes carried out at steps S101, S102,S105 to S108 and steps S113 to S118 of the flowchart shown in FIG. 26are identical with the processes carried out respectively at steps S11,S12, S14 to S17 and steps S21 to S26 of the flowchart shown in FIG. 17.The processes carried out at the steps S101, S102, S105 to S108 andsteps S113 to S118 are not explained in detail.

The flowchart shown in FIG. 26 begins with a step S101 at which thefile-system information generation section 362 reads in file-systeminformation FS. Then, in a process carried out at the next step S102,the file-system information generation section 362 produces a result ofdetermination as to whether or not this write processing is beingcarried out for the first time. If the determination result produced inthe process carried out at the step S102 indicates that this writeprocessing is being carried out for the first time, the flow of theprocessing goes on to a step S103 at which the file-system informationgeneration section 362 drives the recording/reproduction block 53 towrite files into the user area on the recording medium 81. The writtenfiles are files (Stream) supplied to the write section 73 from the ECCencoding section 71 by way of the modulation section 72. The files(Stream) are each a file containing stream data.

To be more specific, as shown in the upper diagram of FIG. 27, thefile-system information generation section 362 drives therecording/reproduction block 53 to write the files (Stream) shown in thefigure into a block B172 set on the recording medium 81 in theformatting processing. The files (Stream) are stream-data files suppliedto the write section 73 from the ECC encoding section 71 by way of themodulation section 72 as described above.

Then, in a process carried out at the next step S104, the file-systeminformation generation section 362 drives the recording/reproductionblock 53 to write files into the user area on the recording medium 81.The written files are files (DB: a database for managing stream datastored in the stream-data files) supplied to the write section 73 fromthe ECC encoding section 71 by way of the modulation section 72.

To be more specific, as shown in the upper diagram of FIG. 27, thefile-system information generation section 362 drives therecording/reproduction block 53 to write the files (DB) shown in thefigure into a block B171 set on the recording medium 81 in theformatting processing. As described above, the written files are files(DB) supplied to the write section 73 from the ECC encoding section 71by way of the modulation section 72.

Then, in a process carried out at the next step S105, as shown in theupper diagram of FIG. 27, the file-system information generation section362 drives the recording/reproduction block 53 to write a main FSreferred to as an FS (Metadata) shown in the figure into the block B171in the user area set on the recording medium 81. Subsequently, in aprocess carried out at the next step S106, the file-system informationgeneration section 362 drives the recording/reproduction block 53 towrite inner-circumference-side information on the structure of thevolume (referred to as ‘Volume Str.’ shown in the figure) and anchorinformation (referred to as ‘Anchor’ shown in the figure) on theinner-circumference side into the block B171 in the user area. Theinner-circumference-side information on the structure of the volume andthe anchor information on the inner-circumference side are pieces ofinformation corresponding to the main FS.

Then, in a process carried out at the next step S107, the file-systeminformation generation section 362 drives the recording/reproductionblock 53 to write an FS (MD-Mirror) shown in the figure as a mirror FSinto a block B173 in the user area.

Subsequently, in a process carried out at the next step S108, thefile-system information generation section 362 drives therecording/reproduction block 53 to write outer-circumference-sideinformation on the structure of the volume and anchor information on theouter-circumference side into the block B173 set in the user area as anarea used for recording outer-circumference-side information on thestructure of the volume and anchor information on theouter-circumference side. The outer-circumference-side information onthe structure of the volume and the anchor information on theouter-circumference side are pieces of information corresponding to themirror FS.

If the determination result produced in the process carried out at thestep S102 indicates that this write processing has been carried out atleast once before, that files have been recorded before at the stepsS103 to S108 and then information is to be incrementally recorded in thefiles or the files are to be updated this time, the flow of theprocessing goes on to a step S109.

In a process carried out at the step S109, the file-system informationgeneration section 362 drives the recording/reproduction block 53 towrite files into the user area on the recording medium 81. The writtenfiles are files (Stream) supplied to the write section 73 from the ECCencoding section 71 by way of the modulation section 72.

To be more specific, as shown in the middle diagram of FIG. 27, thefile-system information generation section 362 drives therecording/reproduction block 53 to write the files (Stream) shown in thefigure as files supplied to the write section 73 from the ECC encodingsection 71 by way of the modulation section 72 into the block B172′ seton the recording medium 81 in the formatting processing, for example, ifinformation has been recorded like in the processing state shown in theupper diagram of FIG. 27. To put it in more detail, in a process toincrementally record information to an already existing file, thefile-system information generation section 362 incrementally records newadditional information in the block B172′ shown in the middle diagram ofFIG. 27, adding the new information to the information already recordedin the block B172 shown in the upper diagram of FIG. 27. In a process torecord a file containing new information as an update of the informationalready recorded in the block B172 shown in the upper diagram of FIG.27, on the other hand, the file already recorded in the block B172 isput in a state of being unreadable and information to be recorded intothe block B172′ is constructed as a newly updated file to be recorded inthe block B172′ adjacent to the block B172.

Then, in a process carried out at the next step S110, the file-systeminformation generation section 362 controls the write section 73 throughthe ECC encoding section 71 and the modulation section 72 to put themain FS referred to as an FS (Metadata), the inner-circumference-sideinformation on the structure of the volume, the anchor information, andthe files (DB) in a state of being unreadable by therecording/reproduction block 53 out from the recording medium 81 asshown in the middle diagram of FIG. 27.

To be more specific, the file-system information generation section 362puts the main FS referred to as an FS (Metadata), theinner-circumference-side information on the structure of the volume, theanchor information on the inner-circumference side and the files (DB) ina state of being unreadable by the recording/reproduction block 53 outfrom the recording medium 81 as shown in the middle diagram of FIG. 27.The files (DB) are defined as database files, which are updated wheninformation is incrementally recorded in the already existing files orwhen the files are updated. The main FS referred to as an FS (Metadata)is file-system information recorded in a block B171.

Then, in a process carried out at the next step S111, the file-systeminformation generation section 362 searches the recording area for aclosest SA area allowing new information to be recorded therein.Generated in a process carried out at the step S110, the new informationto be recorded into the closest SA area is a main FS referred to as anFS (Metadata), inner-circumference-side information on the structure ofthe volume, anchor information on the inner-circumference side and thefiles (DB).

To be more specific, in the case of a single-layer BR-D, an SA area isan area in either the OSA provided on the outer-circumference side orthe ISA provided on the inner-circumference side. In the example shownin the middle diagram of FIG. 27, for example, the closest SA area foundin the search process is an ISA area. Thus, the file-system informationgeneration section 362 selects the ISA area to be used for recording themain FS referred to as an FS (Metadata), the inner-circumference-sideinformation on the structure of the volume, the anchor information onthe inner-circumference side and the files (DB).

Subsequently, in a process carried out at the next step S112, thefile-system information generation section 362 supplies the databasefiles referred to as the files (DB) to the write section 73 to berecorded into an SA area found in the search process carried out at thestep S111. To be more specific, the database files are recorded in ablock B171′ in an area in the ISA, which has been found as the closestSA area in the search process, as shown in the middle diagram of FIG.27.

Then, in a process carried out at the next step S113, the file-systeminformation generation section 362 supplies file-system information tothe write section 73 to be recorded as the main FS by therecording/reproduction block 53 in an SA area found in the searchprocess. To be more specific, as shown in the middle diagram of FIG. 27,for example, the main FS is recorded into the block B171′ in an SA areain the ISA area as shown in the middle diagram of FIG. 27.

Subsequently, in a process carried out at the next step S114, thefile-system information generation section 362 supplies theinner-circumference-side information on the structure of the volume andthe anchor information to the write section 73 to be recorded by therecording/reproduction block 53 into the block B171′ in an SA area asshown in the middle diagram of FIG. 27. The inner-circumference-sideinformation on the structure of the volume and the anchor informationare pieces of information corresponding to the main FS.

Then, in a process carried out at the next step S115, the file-systeminformation generation section 362 controls the write section 73 to putthe mirror FS referred to as an FS (MD-Mirror), theouter-circumference-side information on the structure of the volume andthe anchor information on the outer-circumference side in a state ofbeing unreadable from the block B173 shown in the middle diagram of FIG.27. Subsequently, in a process carried out at the next step S116, thefile-system information generation section 362 searches the recordingarea for a closest SA area allowing new information to be recordedtherein. The new information to be recorded into the closest SA area isa mirror FS, outer-circumference-side information on the structure ofthe volume and anchor information on the outer-circumference side. Inthe example shown in the middle diagram of FIG. 27, for example, theclosest SA area found in the search process is an area in the OSA.

Then, in a process carried out at the next step S117, the file-systeminformation generation section 362 supplies the mirror FS to the writesection 73 to be recorded by the recording/reproduction block 53 in theOSA area found in the search process carried out at the step S116. To bemore specific, the mirror FS is recorded in a block B173′ of the OSA asshown in the middle diagram of FIG. 27.

Subsequently, in a process carried out at the next step S118, thefile-system information generation section 362 supplies theouter-circumference-side information on the structure of the volume andthe anchor information on the outer-circumference side to the writesection 73 to be recorded by the recording/reproduction block 53 in thearea in the OSA. The outer-circumference-side information on thestructure of the volume and the anchor information on theouter-circumference side are pieces of information corresponding to themirror FS. To be more specific, as shown in the middle diagram of FIG.27, the outer-circumference-side information on the structure of thevolume and the anchor information on the outer-circumference side arerecorded in the block B173′ as shown in the middle diagram of FIG. 27.

In addition, in a process to add information to a file already recordedon the recording medium 81 as shown in the middle diagram of FIG. 27 orupdate the already existing file, at the step S109, as shown in thelower diagram of FIG. 27, the file-system information generation section362 drives the recording/reproduction block 53 to write the files(Stream) shown in the into the block B172″ of the user area.

Then, in a process carried out at the next step S110, the file-systeminformation generation section 362 puts the main FS, theinner-circumference-side information on the structure of the volume andthe anchor information in a state of being unreadable as shown in thelower diagram of FIG. 27. The main FS, the inner-circumference-sideinformation on the structure of the volume and the anchor informationare pieces of information already recorded in the block B171′ during theimmediately preceding write processing.

Subsequently, in a process carried out at the next step S111, in thecase of the example shown in the lower diagram of FIG. 27, for example,the file-system information generation section 362 searches therecording area for a closest SA area allowing new information to berecorded therein. Obtained as a result of the process carried out at thestep S110, the new information to be recorded into the closest SA areais a new main FS referred to as an FS (Metadata), newinner-circumference-side information on the structure of the volume andnew anchor information on the inner-circumference side. If the closestSA area is an area in the ISA, the file-system information generationsection 362 selects the area in the ISA as the closest SA area to beused for recording the new main FS referred to as an FS (Metadata), thenew inner-circumference-side information on the structure of the volume,the new anchor information and the new files (DB).

Subsequently, in a process carried out at the next step S112, thefile-system information generation section 362 supplies the databasefiles referred to as the files (DB) to the write section 73 to berecorded into an SA area found in the search process. To be morespecific, the database files are recorded in a block B171″ in an ISAarea, which has been found as an SA area in the search process, as shownin the lower diagram of FIG. 27.

Then, in a process carried out at the next step S113, in the case of theexample shown in the lower diagram of FIG. 27, the file-systeminformation generation section 362 supplies the main FS to the writesection 73 to be recorded in a block B171″ in the ISA.

Subsequently, in a process carried out at the next step S114, in thecase of the example shown in the lower diagram of FIG. 27, thefile-system information generation section 362 supplies theinner-circumference-side information on the structure of the volume andthe anchor information on the inner-circumference side to the writesection 73 to be recorded in the block B171″ in the ISA on the recordingmedium 81.

Then, in a process carried out at the next step S115, in the case of theexample shown in the lower diagram of FIG. 27, the file-systeminformation generation section 362 puts the mirror FS referred to as anFS (MD-Mirror), the outer-circumference-side information on thestructure of the volume and the anchor information on theouter-circumference side in a state of being unreadable. The mirror FS,the outer-circumference-side information on the structure of the volumeand the anchor information on the outer-circumference side are pieces ofinformation already recorded in the block B173′ as shown in the middlediagram of FIG. 27.

Subsequently, in a process carried out at the next step S116, in thecase of the example shown in the lower diagram of FIG. 27, thefile-system information generation section 362 searches the recordingarea for a closest SA area allowing new information to be recordedtherein. The new information to be recorded into the closest SA area isa mirror FS, outer-circumference-side information on the structure ofthe volume and anchor information on the outer-circumference side. Ifthe closest SA area is an area in the OSA, the file-system informationgeneration section 362 selects the area in the OSA as the closest SAarea to be used for recording the new mirror main FS, the newouter-circumference-side information on the structure of the volume andthe new anchor information on the outer-circumference side.

Then, in a process carried out at the next step S117, in the case of theexample shown in the lower diagram of FIG. 27, the file-systeminformation generation section 362 supplies the main FS to the writesection 73 to be recorded in a block B173″ in the OSA area found in thesearch process carried out at the step S116.

Subsequently, in a process carried out at the next step S118, in thecase of the example shown in the lower diagram of FIG. 27, thefile-system information generation section 362 supplies the newouter-circumference-side information on the structure of the volume andthe new anchor information on the outer-circumference side to the writesection 73 to be recorded in the block B173″ in the OSA area.

As described above, in a process to add information to files alreadyrecorded on the recording medium 81 or update the already recordedfiles, database files referred to as files (DB) are recorded in the SAin addition to inner-circumference-side information on the structure ofthe volume and anchor information on the inner-circumference side. Thus,in a read process to reproduce stream data, the stream data can be readout without changing the allocation of the file-system information.

In addition, in the case of recording/reproduction apparatus 22 shown inFIG. 19 or 22, database files referred to as files (DB) can also berecorded in an SA area.

It is needless to say that the information-recording order of theprocesses carried out in the write processing described above can bechanged to provide the same effects. It is desirable, however, to carryout a process to record information onto the recording medium 81continuously in a consistent manner in either the direction from theinner-circumference side to the outer-circumference side or thedirection from the outer-circumference side to the inner-circumferenceside. In this way, the write or read processing can be processed at ahigh speed.

It is to be noted that the information-recording processes carried outat the steps S103 to S109, S112 to S114, S117 and S118 of the flowchartshown in FIG. 26 will be described later in detail.

The above descriptions explain a typical case in which all or some ofupdating information of file-system information, anchor information andinformation on the structure of the volume is recorded sequentially intoan SA area during a process to add information to a file alreadyrecorded on the recording medium 81 or update the already recorded file.In a process to add information to a file already recorded on therecording medium 81 or update the already recorded file, however, all orsome of updating information of file-system information, anchorinformation and information on the structure of the volume can berecorded in an area, which is not limited to an SA area. For example,the information can also be recorded in a user area.

FIG. 28 is a diagram showing the configuration of arecording/reproduction apparatus 22 in which, during a process toincrementally record information in an already existing file or updatethe already existing file, updating information of file-systeminformation, anchor information and information on the structure of thevolume can be recorded in an area, which is not limited to an SA area,that is, the updating information can also recorded in a user area. Itis to be noted that every component included in therecording/reproduction mechanism section 22 shown in FIG. 28 as acomponent identical with its counterpart employed in therecording/reproduction mechanism section 22 shown in FIG. 3 is denotedby the same reference numeral as the counterpart and the explanation ofthe component is properly omitted.

The configuration of the recording/reproduction mechanism section 22shown in FIG. 28 is different from the configuration of therecording/reproduction mechanism section 22 shown in FIG. 3 in that therecording/reproduction mechanism section 22 shown in FIG. 28 employs acontrol section 371 as a substitute for the control section 51 employedin the recording/reproduction mechanism section 22 shown in FIG. 3. Thecontrol section 371 is different from the control section 51 in that thecontrol section 371 employs a file-system information recognitionsection 381 as a substitute for the file-system information recognitionsection 61 employed in the control section 51, a file-system informationgeneration section 382 as a substitute for the file-system informationgeneration section 62 employed in the control section 51, analternation-information management section 383 as substitute for thealternation-information management section 63 employed in the controlsection 51 and an alternation-information generation section 384 as asubstitute for the alternation-information generation section 64employed in the control section 51.

Functions of the file-system information recognition section 381 are thesame as those of the file-system information recognition section 61.

Basic functions of the file-system information generation section 382are the same as those of the file-system information generation section62 except that, in a process to incrementally record information in analready existing file or update an already existing file, thefile-system information generation section 382 records a main FS,inner-circumference-side information on the structure of the volume,anchor information on the inner-circumference side, a mirror FS on theouter-circumference side, outer-circumference-side information on thestructure of the volume and anchor information on theouter-circumference side as alternation information of pre-processinginformation into areas close to the original locations of thepre-processing information. The main FS, the inner-circumference-sideinformation on the structure of the volume, the anchor information onthe inner-circumference side, the mirror FS on the outer-circumferenceside, the outer-circumference-side information on the structure of thevolume and the anchor information on the outer-circumference side arepieces of information obtained as a result of the process toincrementally record information in an already existing file or updatean already existing file. The pre-processing information is a main FS,inner-circumference-side information on the structure of the volume,anchor information on the inner-circumference side, a mirror FS on theouter-circumference side, outer-circumference-side information on thestructure of the volume and anchor information on theouter-circumference side. The main FS, the inner-circumference-sideinformation on the structure of the volume, the anchor information onthe inner-circumference side, the mirror FS on the outer-circumferenceside, the outer-circumference-side information on the structure of thevolume and the anchor information on the outer-circumference side havebeen recorded in their original locations before the process toincrementally record information in an already existing file or updatean already existing file. The close locations can be locations in theuser or SA area. In this way, also in a process to record information ina user area, the file-system information generation section 382 recordsthe actually updated information at another location on the recordingmedium 81 without changing the location in the logical-address space inthe same way as if the information were recorded in an SA area.

It is to be noted that the alternation-information management section383, a memory 383 a, the alternation-information generation section 384and a memory 384 a are identical respectively with thealternation-information management section 63, the memory 63 a, thealternation-information generation section 64 and the memory 64 a, whichare shown in FIG. 3, so that explanations are omitted.

Next, by referring to a flowchart shown in FIG. 29, the followingdescription explains write processing carried out by therecording/reproduction mechanism section 22 shown in FIG. 28 to recordinformation onto the recording medium 81, which has been formatted (orinitialized) in the formatting processing represented by the flowchartshown in FIG. 14. It is to be noted that, since processes carried out atsteps S131 to S137 as well as S139 and S143 of the flowchart shown inFIG. 29 are identical with the processes carried out at steps S11 to S19and step S23 of the flowchart shown in FIG. 17, so the processes are notexplained in detail.

In a process carried out at the step S138, the file-system informationgeneration section 382 drives the recording/reproduction block 53 towrite files into the user area on the recording medium 81. The writtenfiles are files (Stream+DB) supplied to the write section 73 from theECC encoding section 71 by way of the modulation section 72.

To be more specific, as shown in the lower diagram of FIG. 30, thefile-system information generation section 382 drives therecording/reproduction block 53 to write the files (Stream+DB) shown inthe figure as files supplied to the write section 73 from the ECCencoding section 71 by way of the modulation section 72 into a blockB192′ set on the recording medium 81 in the formatting processing, forexample, if information has been recorded like in the state shown in theupper diagram of FIG. 30. To put it in more detail, in a process toincrementally record information in an already existing file, thefile-system information generation section 382 incrementally records newadditional information in the block B192′ shown in the lower diagram ofFIG. 30, adding the new information to the information already recordedin the block B192 shown in the upper diagram of FIG. 30. In a process torecord a file containing new information as an update of the informationalready recorded in the block B192 shown in the upper diagram of FIG.30, on the other hand, the file already recorded in the block B192 isput in a state of being unreadable and information to be recorded intothe block B192′ is constructed as a newly updated file to be recorded inthe block B192′ adjacent to the block B192. It is to be noted that, inthe example shown in the lower diagram of FIG. 30, a file2 (Stream+DB)is a file recorded with a timing different from that of a file1(Stream+DB).

Then, in a process carried out at the next step S140, the file-systeminformation generation section 382 searches the recording area for aclosest user or SA area allowing new information to be recorded therein.The new information to be recorded into the closest user area or SA areais an inner-circumference-side main FS referred to as an FS (Metadata),inner-circumference-side information on the structure of the volume andanchor information on the inner-circumference side. Theinner-circumference-side main FS referred to as an FS (Metadata), theinner-circumference-side information on the structure of the volume andthe anchor information on the inner-circumference side are pieces ofinformation already generated in a process carried out at the step S139to incrementally record information in an already existing file orupdate an already existing file.

In the case of the example shown in the upper diagram of FIG. 30, a freeuser area closest to a block B191 exists at a location adjacent to theblock B191, being separated from B191 in the direction toward theouter-circumference side. A free closest area in the ISA also exists ata location adjacent to the block B191 in the direction toward theinner-circumference side. In the upper diagram of FIG. 30, the free userarea and the free area in the SA exist respectively on the right andleft sides of the block B191. The free user area and the free area inthe SA are each an area that can be used for storing a newinner-circumference-side main FS referred to as an FS (Metadata), newinner-circumference-side information on the structure of the volume andnew anchor information on the inner-circumference side. Let us assumethat the file-system information generation section 382 finds a blockB191′ as the free closest user area as shown in the lower diagram ofFIG. 30. It is to be noted that the block B191′ can also be the closestfree area in the ISA.

Then, in a process carried out at the next step S141, the file-systeminformation generation section 382 supplies the main FS to the writesection 73 by way of the ECC encoding section 71 and the modulationsection 72 to be recorded by the recording/reproduction block 53 in anSA or user area found in the search process carried out at the stepS140.

To be more specific, as shown in the lower diagram of FIG. 30, thefile-system information generation section 382 supplies the main FS onthe inner-circumference side to the write section 73 by way of the ECCencoding section 71 and the modulation section 72 to be recorded in ablock B191′ in the user area on the recording medium 81.

Then, in a process carried out at the next step S142, the file-systeminformation generation section 382 supplies the inner-circumference-sideinformation on the structure of the volume and the anchor information onthe inner-circumference side to the write section 73 by way of the ECCencoding section 71 and the modulation section 72 to be recorded by therecording/reproduction block 53 in a user or SA area found in the searchprocess carried out at the step S140. The inner-circumference-sideinformation on the structure of the volume and the anchor information onthe inner-circumference side are pieces of information corresponding tothe main FS on the inner-circumference side.

To be more specific, the file-system information generation section 382supplies the inner-circumference-side information on the structure ofthe volume and the anchor information on the inner-circumference side tothe write section 73 by way of the ECC encoding section 71 and themodulation section 72 to be recorded in the block B191′ of the user areaon the recording medium 81 as shown in the lower diagram of FIG. 30.

Then, in a process carried out at the next step S144, the file-systeminformation generation section 382 searches the recording area for aclosest SA or user area allowing new information to be recorded therein.The new information to be recorded into the closest SA area is anouter-circumference-side mirror FS referred to as an FS (MD-Mirror),outer-circumference-side information on the structure of the volume andanchor information on the outer-circumference side. The FS (MD-Mirror)on the outer-circumference side, the outer-circumference-sideinformation on the structure of the volume and the anchor information onthe outer-circumference side are pieces of information already generatedin a process carried out at the step S143.

To be more specific, in the example shown in the lower diagram of FIG.30, a block B193′ found as an area closet to the block B193 in thesearch process is an area in the OSA. Thus, the file-system informationgeneration section 382 selects the block B193′ in the OSA as an area tobe used for recording the new outer-circumference-side mirror FSreferred to as an FS (MD-Mirror), the new outer-circumference-sideinformation on the structure of the volume and the new anchorinformation on the outer-circumference side as shown in the lowerdiagram of FIG. 30. On the other hand, the block B193 is an area usedfor storing the previous outer-circumference-side mirror FS referred toas an FS (MD-Mirror), the previous outer-circumference-side informationon the structure of the volume and the anchor information on theouter-circumference side. The block B193′ exists at a location adjacentto the block B191, being separated from the block B191 in the directiontoward the outer-circumference side.

Then, in a process carried out at the next step S145, the file-systeminformation generation section 382 supplies the outer-circumference-sidemirror FS to the write section 73 by way of the ECC encoding section 71and the modulation section 72 to be recorded by therecording/reproduction block 53 in an SA or user area found in thesearch process carried out at the step S144.

To be more specific, the file-system information generation section 382supplies the mirror FS to the write section 73 by way of the ECCencoding section 71 and the modulation section 72 to be recorded in ablock B193′ in the OSA on the recording medium 81 as shown in the lowerdiagram of FIG. 30.

Then, in a process carried out at the next step S146, the file-systeminformation generation section 382 supplies the outer-circumference-sideinformation on the structure of the volume and the anchor information onthe outer-circumference side to the write section 73 by way of the ECCencoding section 71 and the modulation section 72 to be recorded by therecording/reproduction block 53 in the SA or user area found in thesearch process carried out at the step S144. Theouter-circumference-side information on the structure of the volume andthe anchor information on the outer-circumference side are pieces ofinformation corresponding to the mirror FS.

To be more specific, the file-system information generation section 382supplies the outer-circumference-side information on the structure ofthe volume and the anchor information on the outer-circumference side tothe write section 73 by way of the ECC encoding section 71 and themodulation section 72 to be recorded in a block B193′ in the OSA on therecording medium 81 as shown in the lower diagram of FIG. 30.

In the processing carried out as described above in order toincrementally record information in an already existing file or updatean already existing file, pieces of updating information includingfile-system information, information on the structure of the volume andanchor information are recorded sequentially in alternate sectors in aclosest user or SA area. Thus, in spite of the fact that the pieces ofupdating information including file-system information, information onthe structure of the volume and anchor information are recorded atlocations physically different from their original locations,information can be recorded onto the recording medium without modifyingthe logical addresses of the file-system information, the information onthe structure of the volume and the anchor information. In addition, itis no longer necessary to change the logical addresses of thefile-system information, the information on the structure of the volume,the anchor information and other information for every process toincrementally record information in an already existing file or updatean already existing file. As a result, even for a recording mediumallowing no overwriting of data on the same location as is the case witha write-once recording medium, information that must be recorded at afixed location in the logical-address space appears like informationtreatable in a way as if overwriting were permitted. In addition, in aprocess to incrementally record information in an already existing fileor update an already existing file, pieces of updating informationincluding file-system information, information on the structure of thevolume and anchor information can be recorded in a closest user or SAarea as described above. Thus, if necessary, an SA area providedoriginally as an alternate area of an area with a defective sectordetected in a recording medium can be used in a process to incrementallyrecord information in an already existing ordinary file or update analready existing ordinary file while assuring an area in the SA for itsoriginal purpose.

In the example described above, management information is recorded inclosest areas at locations adjacently separated from areas used forrecording previous management area in the direction toward theouter-circumference side. It is to be noted, however, that themanagement information can also be recorded in closest areas atlocations adjacently separated from the areas used for recordingprevious management area in the direction toward the inner-circumferenceside. The information-recording processes carried out at the steps S133to S138 as well the steps S141, S142, S145 and S146 of the flowchartshown in FIG. 29 will be described in more detail later.

The above descriptions explain a case in which during the processingcarried out in order to incrementally record information in an alreadyexisting file or update an already existing file, pieces of updatinginformation including file-system information, information on thestructure of the volume and anchor information are recorded sequentiallyin alternate sectors in a closest user or SA area. However, it is alsopossible to provide a configuration in which a dedicated SRR is providedas an area used for recording each of the file-system information,information on the structure of the volume and anchor information and,in a process to incrementally record information in an already existingfile or update an already existing file, pieces of updating informationincluding file-system information, information on the structure of thevolume and anchor information are each recorded in a free area in adedicated SRR allocated to the information. It is to be noted that, inthis case, if a free area no longer exists in a dedicated SRR, theinformation to which the dedicated SRR is allocated can be recorded inan SA area.

FIG. 31 is a diagram showing the configuration of arecording/reproduction apparatus 22 in which a dedicated SRR is providedas an area used for recording each of the file-system information,information on the structure of the volume and anchor information and,in a process to incrementally record information in an already existingfile or update an already existing file, pieces of updating informationincluding file-system information, information on the structure of thevolume and anchor information are each recorded in a free area in adedicated SRR allocated to the information. It is to be noted that everycomponent included in the recording/reproduction mechanism section 22shown in FIG. 31 as a component identical with its counterpart employedin the recording/reproduction mechanism section 22 shown in FIG. 3 isdenoted by the same reference numeral as the counterpart and theexplanation of the component is properly omitted.

The configuration of the recording/reproduction mechanism section 22shown in FIG. 31 is different from the configuration of therecording/reproduction mechanism section 22 shown in FIG. 3 in that therecording/reproduction mechanism section 22 shown in FIG. 31 employs acontrol section 391 as a substitute for the control section 51 shown inFIG. 3. The control section 391 is different from the control section 51in that the control section 391 employs a file-system informationrecognition section 401 as a substitute for the file-system informationrecognition section 61 employed in the control section 51, a file-systeminformation generation section 402 as a substitute for the file-systeminformation generation section 62 employed in the control section 51, analternation-information management section 403 as substitute for thealternation-information management section 63 employed in the controlsection 51 and an alternation-information generation section 404 as asubstitute for the alternation-information generation section 64employed in the control section 51.

Functions of the file-system information recognition section 401 are thesame as those of the file-system information recognition section 61.

Basic functions of the file-system information generation section 402are the same as those of the file-system information generation section62 except that, in a process to newly record a file, the file-systeminformation generation section 402 records a main FS,inner-circumference-side information on the structure of the volume,anchor information on the inner-circumference side, a mirror FS,outer-circumference-side information on the structure of the volume andanchor information on the outer-circumference side in a dedicated SRRallocated to each of the pieces of information. In a process toincrementally record information in an already existing file or updatean already existing file, on the other hand, the file-system informationgeneration section 402 records a main FS, inner-circumference-sideinformation on the structure of the volume, anchor information on theinner-circumference side, a mirror FS, outer-circumference-sideinformation on the structure of the volume and anchor information on theouter-circumference side as replacement information of pre-processinginformation into an area in a dedicated SRR allocated to each of thepieces of information. The main FS, the inner-circumference-sideinformation on the structure of the volume, the anchor information onthe inner-circumference side, the mirror FS, theouter-circumference-side information on the structure of the volume andthe anchor information on the outer-circumference side are pieces ofinformation obtained as a result of the process to incrementally recordinformation in an already existing file or update an already existingfile. Recorded in their original locations before the process toincrementally record information in an already existing file or updatean already existing file, the pre-processing information is a main FS,inner-circumference-side information on the structure of the volume,anchor information on the inner-circumference side, a mirror FS,outer-circumference-side information on the structure of the volume andanchor information on the outer-circumference side. The area in adedicated SRR can be an area in the user or SA area. In this way, alsoin a process to record information in a user area, the file-systeminformation generation section 402 records the actually updatedinformation at another location on the recording medium 81 withoutchanging the location in the logical-address space in the same way as ifthe information were recorded in an SA area.

It is to be noted that the alternation-information management section403, a memory 403 a, the alternation-information generation section 404and a memory 404 a are identical respectively with thealternation-information management section 63, the memory 63 a, thealternation-information generation section 64 and the memory 64 a, whichare employed in the recording/reproduction apparatus 22 shown in FIG. 3,so that explanations are omitted.

Next, by referring to a flowchart shown in FIG. 32, the followingdescription explains write processing carried out by therecording/reproduction mechanism section 22 shown in FIG. 31 to recordinformation onto the recording medium 81, which has been formatted (orinitialized) in the formatting processing represented by the flowchartshown in FIG. 14.

The flowchart shown in FIG. 32 begins with a step S161 at which thefile-system information generation section 402 generates file-systeminformation on the basis of information such as the attribute of a file,in which information is to be incrementally recorded, or a file to beupdated and fetches the generated file-system information.

Then, in a process carried out at the next step S162, the file-systeminformation generation section 402 produces a result of determination asto whether or not this write processing is being carried out for thefirst time.

If the determination result produced in the process carried out at thestep S162 indicates that this write processing is being carried out forthe first time, the flow of the processing goes on to a step S163 atwhich the file-system information generation section 402 drives therecording/reproduction block 53 to write files into dedicated SRRs inthe user area on the recording medium 81. The written files are files(Stream+DB) supplied to the write section 73 from the ECC encodingsection 71 by way of the modulation section 72. The files (Stream+DB)are files (Stream) shown in FIG. 33 as files each containing stream dataand files (DB) shown in the same figure as files each containing adatabase used for controlling the stream data.

To be more specific, as shown in the upper diagram of FIG. 33, thefile-system information generation section 402 drives therecording/reproduction block 53 to write the files (Stream) shown in thefigure as files supplied to the write section 73 from the ECC encodingsection 71 by way of the modulation section 72 into the block B204 in adedicated SRR 504 set among areas on the recording medium 81 in theformatting processing as an SRR used for recording the files (Stream),and write the files (BD management) shown in the figure as filessupplied to the write section 73 from the ECC encoding section 71 by wayof the modulation section 72 into the block B203 in a dedicated SRR 503set among areas on the recording medium 81 in the formatting processingas an SRR used for recording the files (BD management). It is to benoted that, as described earlier, FIG. 33 shows a typical case in whichthe recording medium 81 is a single-layer BD-R.

Then, in a process carried out at the next step S164, the file-systeminformation generation section 402 drives the recording/reproductionblock 53 to write a main FS supplied to the write section 73 from theECC encoding section 71 by way of the modulation section 72 into adedicated SRR 502 set in the user area as an SRR used for recording themain FS on the recording medium 81.

To be more specific, as shown in the upper diagram of FIG. 33, thefile-system information generation section 402 drives therecording/reproduction block 53 to write an FS (Metadata) shown in thefigure as file-system information supplied to the write section 73 fromthe ECC encoding section 71 by way of the modulation section 72 into ablock B202 in the dedicated SRR 502 set on the recording medium 81 inthe formatting processing as an SRR used for recording the main FS.

Then, in a process carried out at the next step S165, the file-systeminformation generation section 402 drives the recording/reproductionblock 53 to write inner-circumference-side information on the structureof the volume and anchor information on the inner-circumference sideinto a dedicated SRR set in the user area on the recording medium 81.The inner-circumference-side information on the structure of the volumeand the anchor information on the inner-circumference side are pieces ofinformation supplied to the write section 73 from the ECC encodingsection 71 by way of the modulation section 72.

To be more specific, as shown in the upper diagram of FIG. 33, thefile-system information generation section 402 drives therecording/reproduction block 53 to write ‘Volume Str.’ and ‘Anchor’shown in the figure as respectively the inner-circumference-sideinformation on the structure of the volume and the anchor information onthe inner-circumference side into a block B201 in a dedicated SRR 501set on the recording medium 81 in the formatting processing as an SRR501 used for the recording inner-circumference-side information on thestructure of the volume and the anchor information on theinner-circumference side. Supplied to the write section 73 from the ECCencoding section 71 by way of the modulation section 72, theinner-circumference-side information on the structure of the volume andthe anchor information on the inner-circumference side are pieces ofinformation corresponding to the main FS.

Then, in a process carried out at the next step S166, the file-systeminformation generation section 402 drives the recording/reproductionblock 53 to write a mirror FS supplied to the write section 73 from theECC encoding section 71 by way of the modulation section 72 into adedicated SRR in the user area set on the recording medium 81.

To be more specific, as shown in the upper diagram of FIG. 33, thefile-system information generation section 402 drives therecording/reproduction block 53 to write an FS (MD-Mirror) shown in thefigure as file-system information supplied to the write section 73 fromthe ECC encoding section 71 by way of the modulation section 72 into ablock B205 in a dedicated SRR 505 set on the recording medium 81 in theformatting processing as an SRR used for recording the mirror FS.

Then, in a process carried out at the next step S167, the file-systeminformation generation section 402 drives the recording/reproductionblock 53 to write outer-circumference-side information on the structureof the volume and anchor information, which are supplied to the writesection 73 from the ECC encoding section 71 by way of the modulationsection 72, into a dedicated SRR in the user area set on the recordingmedium 81.

To be more specific, as shown in the upper diagram of FIG. 33, thefile-system information generation section 402 drives therecording/reproduction block 53 to write ‘Volume Str.’ and ‘Anchor’shown in the figure as respectively the outer-circumference-sideinformation on the structure of the volume and the anchor informationinto a block B206 in a dedicated SRR 506 set on the recording medium 81in the formatting processing as a dedicated SRR used for recording theouter-circumference-side information on the structure of the volume andthe anchor information. Supplied to the write section 73 from the ECCencoding section 71 by way of the modulation section 72, theouter-circumference-side information on the structure of the volume andthe anchor information are pieces of information corresponding to themirror FS.

If the determination result produced in the process carried out at thestep S162 indicates that this write processing has been carried out atleast once before at the steps S163 to S167, on the other hand, the flowof the processing goes on to a step S168.

In a process carried out at the step S168, the file-system informationgeneration section 402 drives the recording/reproduction block 53 towrite files into dedicated SRRs in the user area on the recording medium81. The written files are stream data (Files (stream) shown in FIG. 33)and database (Files (BD management) also shown in the figure) formanaging the stream data. These files are supplied to the write section73 from the ECC encoding section 71 by way of the modulation section 72.

To be more specific, as shown in the lower diagram of FIG. 33, thefile-system information generation section 402 drives therecording/reproduction block 53 to write the files (Files (Stream) andFiles (BD management) shown in the figure) as files supplied to thewrite section 73 from the ECC encoding section 71 by way of themodulation section 72 into a block B204′ in a dedicated SRR 504 and ablock B203′ in a dedicated SRR 503 respectively, set on the recordingmedium 81 in the formatting processing, for example, if information hasbeen recorded like in the processing state shown in the upper diagram ofFIG. 33. To put it in more detail, in a process to incrementally recordinformation (Added Files (stream) in the figure) in already existingfiles (Stream), the file-system information generation section 402incrementally records new additional information in the block B204′ ofthe dedicated SRR 504 shown in the lower diagram of FIG. 33, adding thenew information to the information already recorded in the block B204 ofthe dedicated SRR 504 shown in the upper diagram of FIG. 33. In aprocess to record a file containing new information (Added Files (BDmanagement)) as an update of the files already recorded in the blockB203 of the dedicated SRR 503 shown in the upper diagram of FIG. 33, onthe other hand, the files already recorded in the block B203 of thededicated SRR 503 are put in a state of being unreadable, andinformation to be recorded into the block B203′ of the dedicated SRR 503is constructed as a newly updated file to be recorded in the block B203′adjacent to the block B203 in the SRR 503.

Then, in a process carried out at the next step S169, the file-systeminformation generation section 402 controls the write section 73 throughthe ECC encoding section 71 and the modulation section 72 to put theinner-circumference-side main FS referred to as an FS (Metadata), theinner-circumference-side information on the structure of the volume andthe anchor information in a state of being unreadable by therecording/reproduction block 53 out from the recording medium 81.

To be more specific, the file-system information generation section 402puts the main FS referred to as an FS (Metadata) recorded in the blockB202 in the dedicated SRR 502 as shown in the lower diagram of FIG. 33and the inner-circumference-side information on the structure of thevolume and the anchor information in a state of being unreadable by therecording/reproduction block 53 out from the recording medium 81. Theinner-circumference-side information on the structure of the volume andthe anchor information are pieces of information already recorded in theblock B201 of the dedicated SRR 501 as shown in the lower diagram ofFIG. 33. It is to be noted that, in the diagrams shown in FIG. 33, anarea put in a state of being unreadable by the recording/reproductionblock 53 out from the recording medium 81 is shown as a black box markedwith white characters. An unreadable area mentioned in the followingdescription is also shown in figures as such a black box.

Then, in a process carried out at the next step S170, the file-systeminformation generation section 402 searches each of the dedicated SRRsfor a closest location allowing new information to be recorded therein.The new information to be recorded into the closest location is aninner-circumference-side main FS referred to as an FS (Metadata) andinner-circumference-side information on the structure of the volume andanchor information to which the dedicated SRRs are allocated. The mainFS referred to as an FS (Metadata), the information on the structure ofthe volume and the anchor information have been generated in a processcarried out at the step S169 to incrementally record information in analready existing file or update an already existing file.

To be more specific, in the case of the example of shown in the upperdiagram of FIG. 33, the closest location found in the search processcarried out by the file-system information generation section 402 as alocation allowing the new FS (Metadata) to be recorded in the SRR 502allocated to main FSes is a block B202′ adjacent to the block B202provided in the dedicated SRR 502 as an area used for recording the mainFS, which has been put in a state of being unreadable from the blockB202 as shown in the lower diagram of FIG. 33. By the same token, theclosest location found in the search process carried out by thefile-system information generation section 402 as a location allowingnew inner-circumference-side information on the structure of the volumeand new anchor information to be recorded in the SRR 501 allocated toinner-circumference-side information on the structure of the volume andanchor information is a block B201′ adjacent to the block B201 providedin the dedicated SRR 501 as an area used for recording theinner-circumference-side information on the structure of the volume andthe anchor information as shown in the lower diagram of FIG. 33. Theblock B201 is put in a state of being unreadable.

Then, in a process carried out at the next step S171, the file-systeminformation generation section 402 produces a result of determination asto whether or not the dedicated SRR 502 allocated toinner-circumference-side main FSes includes a free area allowing a newmain FS on the inner-circumference side to be recorded therein. Sincethe dedicated SRR 502 includes such a free area in the case of theexample shown in FIG. 33, the flow of the processing goes on to a stepS172.

In a process carried out at the step S172, the file-system informationgeneration section 402 supplies the main FS on the inner-circumferenceside to the write section 73 by way the ECC encoding section 71 and themodulation section 72 to be recorded by the recording/reproduction block53 in the free area found in the search process carried out at the stepS170.

To be more specific, as shown in the lower diagram of FIG. 33, thefile-system information generation section 402 supplies the newfile-system information to the write section 73 by way the ECC encodingsection 71 and the modulation section 72 to be recorded in a block B202′in the dedicated SRR 502 on the recording medium 81.

Then, in a process carried out at the next step S174, the file-systeminformation generation section 402 produces a result of determination asto whether or not the dedicated SRR 501 allocated toinner-circumference-side information on the structure of the volume andanchor information includes a free area allowing new information on thestructure of the volume and new anchor information to be recordedtherein. Since the dedicated SRR 501 includes such a free area in thecase of the example shown in FIG. 33, the flow of the processing goes onto a step S175.

In a process carried out at the step S175, the file-system informationgeneration section 402 supplies the new inner-circumference-sideinformation on the structure of the volume and the new anchorinformation corresponding to the main FS to the write section 73 by waythe ECC encoding section 71 and the modulation section 72 to be recordedby the recording/reproduction block 53 in the free area found in thesearch process carried out at the step S170 as an area in a dedicatedSRR allocated to information on the structure of the volume and newanchor information.

To be more specific, as shown in the lower diagram of FIG. 33, thefile-system information generation section 402 supplies the newinner-circumference-side information on the structure of the volume andthe new anchor information to the write section 73 by way the ECCencoding section 71 and the modulation section 72 to be recorded in ablock B201′ in the dedicated SRR 501 set on the recording medium 81 asan SRR allocated to inner-circumference-side information on thestructure of the volume and anchor information.

Then, in a process carried out at the next step S177, the file-systeminformation generation section 402 controls the write section 73 throughthe ECC encoding section 71 and the modulation section 72 to put theouter-circumference-side mirror FS referred to as an FS (MD-Mirror), theinformation on the structure of the volume and the anchor information ina state of being unreadable by the recording/reproduction block 53 outfrom the recording medium 81. The FS (MD-Mirror), the information on thestructure of the volume and the anchor information have been recorded indedicated SRRs allocated to the outer-circumference-side mirror FS, theinformation on the structure of the volume and the anchor information.

To be more specific, as shown in the lower diagram of FIG. 33, thefile-system information generation section 402 puts the FS (MD-Mirror)recorded in a block B205 of a dedicated SRR 505 as well as theinformation on the structure of the volume and the anchor informationrecorded in the block B206 of a dedicated SRR 506 in a state of beingunreadable by the recording/reproduction block 53 out from the recordingmedium 81.

Then, in a process carried out at the next step S178 corresponding tothe process at the step S177, the file-system information generationsection 402 searches dedicated SRRs for a closest user or SA areaallowing new information to be recorded therein. The new information tobe recorded into the closest user or SA area is anouter-circumference-side mirror FS, information on the structure of thevolume and anchor information.

To be more specific, in the case of the example of shown in the upperdiagram of FIG. 33, the closest location found in the search processcarried out by the file-system information generation section 402 as alocation allowing a new outer-circumference-side mirror FS referred toas the FS (MD-Mirror) to be recorded in the SRR 505 allocated to mirrorFSes is a block B205′ adjacent to the block B205 provided in thededicated SRR 505, which has been put in a state of being unreadable asshown in the diagram of FIG. 33. By the same token, the closest locationfound in the search process carried out by the file-system informationgeneration section 402 as a location allowing newouter-circumference-side information on the structure of the volume andnew anchor information to be recorded in the SRR 506 allocated toinformation on the structure of the volume and anchor information is ablock B206′ adjacent to the block B206 provided in the dedicated SRR506, which has been put in a state of being unreadable, as shown in thediagram of FIG. 33.

Then, in a process carried out at the next step S179, the file-systeminformation generation section 402 produces a result of determination asto whether or not the dedicated SRR 505 allocated to mirror FSesincludes a free area allowing a new outer-circumference-side mirror FSto be recorded therein. Since the dedicated SRR 505 includes such a freearea in the case of the example shown in FIG. 33, the flow of theprocessing goes on to a step S180.

In a process carried out at the step S180, the file-system informationgeneration section 402 supplies the outer-circumference-side mirror FSto the write section 73 by way the ECC encoding section 71 and themodulation section 72 to be recorded by the recording/reproduction block53 in the free area found in the search process carried out at the stepS178.

To be more specific, as shown in the lower diagram of FIG. 33, thefile-system information generation section 402 supplies the newfile-system information to the write section 73 by way the ECC encodingsection 71 and the modulation section 72 to be recorded in the blockB205′ of the dedicated SRR 505 on the recording medium 81.

Then, in a process carried out at the next step S182, the file-systeminformation generation section 402 supplies the outer-circumference-sideinformation on the structure of the volume and the anchor informationcorresponding to the mirror FS to the write section 73 by way of the ECCencoding section 71 and the modulation section 72 to be recorded by therecording/reproduction block 53 in an OSA area found in the searchprocess carried out at the step S178.

To be more specific, the file-system information generation section 402supplies the outer-circumference-side information on the structure ofthe volume and the anchor information to be recorded in the block B206′of the OSA on the recording medium 81 as shown in the lower diagram ofFIG. 33.

For example, if recorded main FSes on the inner-circumference sideoccupy the block B202 in the entire dedicated SRR 502 allocated to mainFSes as shown in the upper diagram of FIG. 34, on the other hand, theblock B202 in the entire dedicated SRR 502 will become an unreadablearea in the process carried out at the step S169 so that the SRR 502will no longer include a free area used for recording a new main FS asshown in the lower diagram of FIG. 34. In this case, the determinationresult produced in the process carried out at the step S171 indicatesthat the SRR 502 does not include such a free area, causing the flow ofthe processing to go on to the step S173.

In a process carried out at the step S173, the file-system informationgeneration section 402 supplies the main FS to the write section 73 byway the ECC encoding section 71 and the modulation section 72 to berecorded by the recording/reproduction block 53 in a closest SA area.

To be more specific, as shown in the lower diagram of FIG. 34, thefile-system information generation section 402 supplies the newfile-system information to the write section 73 by way the ECC encodingsection 71 and the modulation section 72 to be recorded in the blockB202′ in the ISA on the recording medium 81.

By the same token, for example, if recorded information on the structureof the volume and recorded anchor information corresponding to the mainFS occupy the block B201 in the entire dedicated SRR 501 allocated toinformation on the structure of the volume and anchor information asshown in the upper diagram of FIG. 34, on the other hand, the block B201in the entire dedicated SRR 501 will become an unreadable area in theprocess carried out at the step S169 so that the SRR 501 will no longerinclude a free area used for recording new information on the structureof the volume and new anchor information as shown in the lower diagramof FIG. 34. In this case, the determination result produced in theprocess carried out at the step S174 indicates that the SRR 501 does notinclude such a free area, causing the flow of the processing to go on tothe step S176.

In a process carried out at the step S176, the file-system informationgeneration section 402 supplies new inner-circumference-side informationon the structure of the volume and new anchor information correspondingto the main FS to the write section 73 by way the ECC encoding section71 and the modulation section 72 to be recorded by therecording/reproduction block 53 in a closest SA area.

To be more specific, as shown in the lower diagram of FIG. 34, thefile-system information generation section 402 supplies the newinner-circumference-side information on the structure of the volume andthe new anchor information to the write section 73 by way the ECCencoding section 71 and the modulation section 72 to be recorded in theblock B201′ in the ISA on the recording medium 81.

In addition, for example, if recorded mirror FSes occupy the block B205in the entire dedicated SRR 505 allocated to mirror FSes as shown in theupper diagram of FIG. 34, on the other hand, the block B205 in theentire dedicated SRR 505 will become an unreadable area in the processcarried out at the step S177 so that the SRR 505 will no longer includea free area used for recording a new mirror FS as shown in the lowerdiagram of FIG. 34. In this case, the determination result produced inthe process carried out at the step S179 indicates that the SRR 505 doesnot include such a free area, causing the flow of the processing to goon to the step S181.

In a process carried out at the step S181, the file-system informationgeneration section 402 supplies the mirror FS to the write section 73 byway the ECC encoding section 71 and the modulation section 72 to berecorded by the recording/reproduction block 53 in a closest SA area.

To be more specific, as shown in the lower diagram of FIG. 34, thefile-system information generation section 402 supplies the newfile-system information to the write section 73 by way the ECC encodingsection 71 and the modulation section 72 to be recorded in the blockB205′ in the OSA on the recording medium 81.

It is to be noted that the information-recording processes carried outat the steps S163 to S168, S172, S173, S175, S176 and S180 to S182 ofthe flowchart shown in FIG. 32 will be described in more detail later.

In the processing carried out as described above in order toincrementally record information in an already existing file or updatean already existing file, pieces of updating information includingincrementally recorded or updated file-system information, informationon the structure of the volume and anchor information are writtensequentially in SRRs as replacements of the pre-updating file-systeminformation, the information on the structure of the volume and theanchor information. Thus, in spite of the fact that the pieces ofupdating information including the incrementally recorded or updatedfile-system information, the information on the structure of the volumeand the anchor information are recorded at locations physicallydifferent from their original locations, information can be recordedonto the recording medium without modifying the logical addresses of therecorded file-system information, the information on the structure ofthe volume and the anchor information. In addition, it is no longernecessary to change the logical addresses of the file-systeminformation, the information on the structure of the volume, the anchorinformation and other for every process to incrementally recordinformation in an already existing file or update an already existingfile. As a result, even for a recording medium allowing no overwritingof data on the same location as is the case with a write-once recordingmedium, information that must be recorded at a fixed location in thelogical-address space appears like information treatable in a way as ifoverwriting were permitted.

In addition, pieces of data to be recorded in a process to incrementallyrecord information in an already existing file or update an alreadyexisting file are written basically in user areas in dedicated SRRsrespectively allocated to the pieces of data. It is thus possible toprevent the SA area, which is to be used naturally when a defectivesector on the recording medium 81 is detected, from being utilizedwastefully. On top of that, when the dedicated SRRs each no longer havea sufficient size due to repeated execution of the process toincrementally record information in an already existing file or updatean already existing file, the SA area can be used. Thus, the SA area canbe used effectively in the process of recording data while it ispossible to prevent the SA area from being utilized wastefully.

The following description explains the information-recording processescarried out at the steps S13 to S18 as well as the steps S21, S22, S25and S26 of the flowchart shown in FIG. 17, the information-recordingprocesses carried out at the steps S43 to S48 as well as the steps S50,S51, S54 and S55 of the flowchart shown in FIG. 20, theinformation-recording processes carried out at the steps S73 to S77 aswell the steps S79, S80 and S83 of the flowchart shown in FIG. 23, theinformation-recording processes carried out at the steps S103 to S109,S112 to S114, S117 and S118 of the flowchart shown in FIG. 26, theinformation-recording processes carried out at the steps S133 to S138 aswell the steps S141, S142, S145 and S146 of the flowchart shown in FIG.29 and the information-recording processes carried out at the steps S163to S168, S172, S173, S175, S176 and S180 to S182 of the flowchart shownin FIG. 32 in detail as follows.

Each of the above information-processing processes is carried out asalternation-information management processing followed by actualinformation-recording processing. The alternation-information managementprocessing is carried out to generate a temporary DL (Defect List),which is a list of alternate-management pairs each provided for an ECCcluster of data of a file being overwritten or updated. Analternate-management pair is a pair of an alternation original locationand an alternation replacement location. On the other hand, the actualinformation-recording processing is carried out to rearrange the orderof the pairs each including an alternation original location and analternation replacement location to generate a DL to be eventuallyrecorded onto the recording medium 81 and to actually record the dataonto the recording medium 81. In the following description, the DL to beeventually recorded onto the recording medium 81 is referred to as afinal DL.

First of all, the alternation-information management processing isexplained by referring to a flowchart shown in FIG. 35.

The flowchart begins with a step S201 at which thealternation-information management section 63 produces a result ofdetermination as to whether or not a cluster is to be overwritten orupdated. This process is carried out repeatedly till the result ofdetermination indicates that a cluster is to be overwritten or updated.As the result of determination indicates that a cluster is to beoverwritten or updated, the flow of the processing goes on to a stepS202. An example leading to such a result of determination is explainedas follows. In the process carried out at the step S21 of the flowchartshown in FIG. 17 to record a main FS into an SA area, for example, themain FS recorded in a block B111 shown in FIG. 18 as an alternationoriginal location is updated into a main FS recorded in a block B111′shown in FIG. 18 as an alternation replacement location.

Then, in a process carried out at the next step S202, thealternation-information management section 63 verifies alternationoriginal locations of predetermined clusters containing data of a filebeing overwritten or updated. For example, a cluster to be overwrittenor updated is a cluster at an alternation original address A as shown inthe upper diagram of FIG. 36. In this case, the alternation-informationmanagement section 63 verifies the alternation original address A as thealternation original location. It is to be noted that, at the left uppercorner of FIG. 36, each box represents data of one cluster. Notations Aand B each represent an address of the location of a cluster. In thedirection toward the right side in the figure, the value of the addressincreases by 1 from box to box, that is, from cluster to cluster. To bemore specific, the address increases from A to (A+1), from (A+1) to(A+2) and so on, or the address increases from B to (B+1), from (B+1) to(B+2) and so on. A box hatched with slanting lines represents a clusterwith data actually relocated therein and a black box shown in FIG. 37represents a cluster with no data actually relocated therein.

Then, in a process carried out at the next step S203, thealternation-information management section 63 sets the alternationreplacement locations of the predetermined clusters containing data ofthe file being overwritten or updated and records the data at thelocations. For example, the alternation original location is A and thealternation replacement location is B as shown at the left upper cornerof FIG. 36. In this case, the data is stored at the location B servingas the alternation replacement location in the memory 63 a.

Then, in a process carried out at the next step S204, thealternation-information management section 63 produces a result ofdetermination as to whether or not an error has been generated in theprocess carried out at the step S203. If the result of determinationindicates that no error has been generated in the process carried out atthe step S203, on the other hand, the flow of the processing goes on toa step S205.

Subsequently, in a process carried out at the step S205, thealternation-information management section 63 verifies alternationoriginal locations of predetermined clusters containing data of a filebeing overwritten or updated.

Then, in a process carried out at the next step S206, thealternation-information management section 63 updates a DL generated ina formatting process and stored in the memory 63 a on the basis of thealternation original and alternation replacement addresses of thepredetermined clusters containing data of the file being overwritten orupdated. Subsequently, the flow of the processing goes back to the stepS201.

In the present case, for example, the alternation original addresses andthe alternation replacement addresses are as shown in the upper list atthe upper right corner of FIG. 36. It is to be noted that the leftmostcolumn on the upper list at the upper right corner of FIG. 36 is analternation original column followed by an alternation replacementcolumn in the middle. The alternation replacement column is followed bya cluster range column on the rightmost side. The first row of the upperlist at the upper right corner of FIG. 36 shows that the address ofalternation original location is A, the address of the alternationreplacement location is B and these addresses are each the address ofone cluster. To be more specific, the cluster starting from a locationpointed to by the alternation replacement address B is the alternatecluster of the cluster starting from a location pointed to by thealternation original address A. In the case of the example shown at theupper left corner of FIG. 36, the processes of the steps S202 to S206are carried out repeatedly four times to generate the upper list shownat the upper right corner of FIG. 36. To put it in detail, as shown inthe example at the left upper corner of FIG. 36 and the upper list atthe right upper corner of the figure, data to be overwritten on thecluster starting from a location pointed to by the alternation originaladdress A or data be used as an update of the data of this cluster isactually recorded at a cluster starting from a location pointed to bythe alternation replacement address B. Likewise, data to be overwrittenon the cluster starting from a location pointed to by the alternationoriginal address (A+1) or data be used as an update of the data of thiscluster is actually recorded at a cluster starting from a locationpointed to by the alternation replacement address (B+1). By the sametoken, data to be overwritten on the cluster starting from a locationpointed to by the alternation original address (A+2) or data be used asan update of the data of this cluster is actually recorded at a clusterstarting from a location pointed to by the alternation replacementaddress (B+2). In the same way, data to be overwritten on the clusterstarting from a location pointed to by the alternation original address(A+3) or data be used as an update of the data of this cluster isactually recorded at a cluster starting from a location pointed to bythe alternation replacement address (B+3).

Furthermore, let us assume that the data of only the cluster startingfrom a location indicated by the address (A+2) in the state shown at theupper left corner of FIG. 36 is overwritten as shown at the upper leftcorner of FIG. 37. In this case, in a process carried out at the stepS202 of the flowchart shown in FIG. 35, the alternation original addressis verified to be (A+2) and, in a process carried out at the step S203of the flowchart shown in FIG. 35, the alternation replacement addressis verified to be D instead of (B+2). As a result, as shown in the upperlist at the right upper corner of FIG. 37, data to be overwritten on thecluster starting from a location pointed to by the alternation originaladdress (A+2) is actually recorded at a cluster starting from a locationpointed to by the alternation replacement address D. In FIG. 37, thecluster starting from a location pointed to by the alternationreplacement address D is represented by a box hatched with verticallines.

As described before, if the determination result produced in the processcarried out at the step S204 indicates that an error has been generatedin the process carried out at the step S203, the flow of the processinggoes back to the step S203 to repeat the process of the step S203. Forexample, data to be overwritten on the cluster starting from a locationpointed to by the alternation original address (A+2) or data be used asan update of the data of this cluster is actually recorded at a clusterstarting from a location pointed to by the alternation replacementaddress (B+2), but an error caused by some reasons may be detected asshown in an example at the upper left corner of FIG. 38. In this case,the process of the step S203 is carried out again to actually record thedata to be overwritten on the cluster starting from a location pointedto by the alternation original address (A+2) this time at a clusterstarting from a location pointed to by an alternation replacementaddress of C instead of the alternation replacement address (B+2). Inaddition, information recorded on the temporary DL stored in the memory63 a is corrected to indicate that the cluster starting from a locationpointed to by the alternation replacement address C is the alternatecluster of the cluster starting from a location pointed to by thealternation original address (A+2) as shown at the upper right corner ofFIG. 38. In FIG. 38, the cluster starting from a location pointed to bythe alternation replacement address C is represented by a box hatchedwith vertical lines.

By carrying out the processing as described above, it is possible togenerate a temporary DL showing information associating an alternationoriginal location with an alternation replacement location at aninformation granularity corresponding to a cluster.

Next, the actual information-recording processing cited above isexplained by referring to a flowchart shown in FIG. 39.

The flowchart begins with a step S221 at which thealternation-information generation section 64 produces a result ofdetermination as to whether or not a command to record data onto therecording medium 81 has been received from the control section 51.Typically, the command to record data onto the recording medium 81 isissued when the size of the memory 63 a can no longer accommodate dataor issued to terminate the alternation-information management processingfor example during the iteration of the process of the step S201 of theflowchart shown in FIG. 35.

If the determination result produced in the process carried out at thestep S221 indicates that a command to record data onto the recordingmedium 81 has been received from the control section 51, the flow of theprocessing goes on to a step S222 at which the alternation-informationgeneration section 64 produces a result of determination as to whetheror not the same track or the same SRR includes both the alternationoriginal location and alternation replacement location. To be morespecific, the alternation-information generation section 64 produces aresult of determination as to whether or not the track including thealternation replacement location is a track (or an SA area) differentfrom the track including the alternation original location. If theresult of determination indicates that both the alternation originallocation and alternation replacement location are not included in thesame track or the same SRR or indicates that the track including thealternation replacement location is a track (or an SA area) differentfrom the track including the alternation original location, the flow ofthe processing goes on to a step S223.

Then, in a process carried out at the next step S223, thealternation-information generation section 64 produces a result ofdetermination as to whether or not the size of the overwriting orupdating file is greater than the size of the file to be overwritten orupdated. If the result of determination indicates that the size of theoverwriting or updating file is not greater than the size of the file tobe overwritten or updated, the flow of the processing goes on to a stepS225.

In a process carried out at the step S225, the alternation-informationgeneration section 64 inquires of the alternation-information managementsection 63 in regard to whether or not information recorded on thetemporary DL as information on clusters is information on contiguousclusters. An example of the information on contiguous clusters is shownat the right and left upper portions of FIG. 36. As shown in the figure,the address of the first cluster at the alternation original area is A,which is followed sequentially by addresses (A+1) to (A+3). By the sametoken, the address of the first cluster at the alternation replacementarea is B, which is followed sequentially by addresses (B+1) to (B+3).The address of the alternation replacement area is incremented by 1 foreach cluster to represent locations of consecutive clusters. In thiscase, the response to the inquiry indicates that information recorded onthe temporary DL as information on clusters is information on contiguousclusters and causes the flow of the processing to go on to a step S227.

In a process carried out at the step S227, the alternation-informationgeneration section 64 generates a final DL and records the final DL inthe memory 64 a. In the final DL, the locations pointed to by thealternation replacement addresses are collected to form a single areapointed to by an address. To put it concretely, the information recordedon the temporary DL at the right upper corner of FIG. 36 is changed toinformation recorded on the final DL at the right lower corner of thefigure. On the final DL at the right lower corner of FIG. 36, a range offour clusters starting with a cluster at the address A at thealternation original area is associated with a range of four clustersstarting with a cluster at the address B at the alternation replacementarea. The range of four clusters starting with a cluster at thealternation original area is pointed to by the address A, and the rangeof four clusters starting with a cluster at the alternation replacementarea is pointed to by the address B. Since the information recorded onthe temporary DL as information associating every alternation originallocations with an alternation replacement location at an informationgranularity corresponding to a cluster is converted into information onan alternation original location and an alternation replacementlocation, which each represent a plurality of contiguous clusters inthis way, the temporary DL can be changed to the final DL to be storedin the memory 64 a as a DL having a smaller size.

Then, in a process carried out at the next step S228, thealternation-information generation section 64 requests the recordingsection 52 to record data based on the final DL stored in the memory 64a onto the recording medium 81 and also record the final DL itself ontothe recording medium 81 as well.

As described above, the final DL is generated on the basis of thetemporary DL as an eventual DL containing a smaller number of listentries. Thus, the size of an area allocated on the recording medium 81to the final DL can be reduced. As a result, the size of an areaallocated on the recording medium 81 to be used by the process torewrite or update a file can also be decreased as well.

The response to the inquiry made at the step S225 may indicate thatinformation recorded on the temporary DL is information on noncontiguousclusters. Examples of the information on noncontiguous clusters areshown at the right and left upper portions of FIGS. 37 and 38. In thetemporary DL shown in FIG. 37, for example, the address of the firstcluster at the alternation original area is A, which is followed by theaddress (A+1) of the second cluster. By the same token, the address ofthe first cluster at the alternation replacement area is B, which isfollowed by address of (B+1) of the second cluster. Although the addressof the third cluster at the alternation original area is (A+2) followedby the address (A+3) of the fourth cluster, the corresponding address atthe alternation replacement area is D and (B+3) respectively. To be morespecific, the third and fourth clusters in the alternation replacementarea are not contiguous clusters. Thus, the flow of the processing goesfrom the step S225 to a step S226.

In a process carried out at the step S226, the alternation-informationgeneration section 64 changes a plurality of noncontiguous alternationreplacement addresses to a plurality of contiguous alternationreplacement addresses on the basis of information recorded on thetemporary DL. To put it concretely, as shown in the lower portion ofFIG. 37, for example, data of the contiguous alternation originalclusters in the address range A to (A+3) is relocated in contiguousalternation replacement clusters in the address range D to (D+3). As aresult, in a process carried out at the following step S227, it ispossible to generate a final DL on which the noncontiguous alternationreplacement clusters are collected at a single location in anothertrack. It is to be noted that, in the resulting final DL shown at thelower right corner of FIG. 37, the address of the first cluster at thealternation original area including four contiguous clusters is A,whereas the address of the first cluster at the alternation replacementarea including four contiguous clusters is D.

As a result, in the same way as what is described above, the size of anarea allocated on the recording medium 81 to be used by the process torewrite or update a file can also be decreased as well.

If the determination result produced in the process carried out at thestep S223 indicates that the size of the overwriting or updating file isgreater than the size of the file to be overwritten or updated, on theother hand, the flow of the processing goes on to a step S224 at whichthe alternation-information generation section 64 records the differencedata obtained as a result of the overwriting process in the alternationoriginal area in a continuation cluster of the original clusters in thealternation original area.

To be more specific, as shown in the upper portion of FIG. 40, a file Ais recorded at an alteration original area ranging from the address A tothe address (A+3). The size of a file A′ generated as a file to beoverwritten on the file A is greater than the size of the file A by acluster starting at an address (A+4) as shown in the middle left portionof FIG. 40. In this case, the alternation-information generation section64 records the difference data between the files A′ and A at the clusterstarting at an address (A+4) as a continuation cluster of the clustersin the alteration original area. The continuation cluster is representedby a lattice-like box shown in the middle left portion of FIG. 40.

The above descriptions are summarized as follows. If an alterationreplacement area is not in the same track, but in another track oranother SA area, as shown in the lower portion of FIG. 40, the logicalarea of the file A is shown as a contiguous area R1 ranging from theaddress A to the address (A+4) even though the physical area of the samefile is represented by two areas, i.e., areas R2-1 and R2-2. Thus, whenthe difference data is read out from the area R2-2 after reading outmain data from the area R2-1 in a process to read out the file A fromthe recording medium 81, it is necessary to reverse the physicaldirection to read the file A with respect to the physical direction inwhich the data of the file A has been recorded in the areas. In aprocess to record the data of the file A, the data has been recorded inthe direction from the area R2-2 to the area R2-1. Thus, when thealternation replacement area does not exist in the same track as thealternation original area, the logical addresses are continuous so that,as file-system processing, management of logical addresses is easy toexecute. However, in this case, the clusters exist not in a physicallycontiguous area and, in addition, it is necessary to reverse thephysical direction to read the file A. As a result, the file A cannot beread out at a high speed.

If the determination result produced in the process carried out at thestep S222 indicates that the same track or the same SRR includes boththe alternation original location and alternation replacement location,on the other hand, the flow of the processing goes on to steps S229 toS231 at which the same process as the steps S225 to S227 are carriedout. Then, at the next step S232, the same process as the step S223 iscarried out. Subsequently, at the next step S233, the same process asthe step S224 is carried out. In a process carried out at the step S233,the alternation-information generation section 64 records the differencedata obtained as a result of the overwriting process in a continuationcluster of the original clusters in the alternation replacement area.

To be more specific, if the alternation replacement area exists in thesame track as the alternation original area, as shown in the middleportion of FIG. 41, for the alteration original area, an alterationreplacement area follows the alteration original area as an alternationreplacement area including four consecutive clusters ranging from anaddress B coinciding with an address (A+4) to an address (B+3). Thedifference data obtained as a result of an overwriting or updatingprocess is recorded in a cluster at an address (B+4) following theaddress (B+3). The cluster at the address (B+4) is shown as a latticebox.

The above descriptions are summarized as follows. If the alternationreplacement area exists in the same track as the alternation originalarea, as shown in the lower portion of FIG. 41, the logical areaincludes an area R1-1 ranging from the address A to the address (A+3)and an area R1-2 at an address (B+4). On the other hand, the physicalarea is a single area R2. In a process to read out the file A from therecording medium 81, data of the file can be read out continuously fromthe area R2 shown in the lower portion of FIG. 41. Thus, since thereading direction can be made the same as the recording direction, thedata can be read out with ease.

As a result, when the alternation replacement area exists in the sametrack as the alternation original area, the logical addresses are notcontinuous so that, as file-system processing, management of logicaladdresses is difficult to execute. Since the physical addresses arecontinuous, however, the file can be read out continuously fromconsecutive locations in a contiguous area at a high speed.

It is to be noted that the final DL shown in the right middle portion ofFIG. 40 is identical with the final DL shown in the right middle portionof FIG. 41 in that, in both the final DLs, the alternation original areaincludes four clusters starting with one at the address A and thealternation replacement area includes four clusters starting with one atthe address B. The final DL shown in the right middle portion of FIG. 40is different from the final DL shown in the right middle portion of FIG.41 in that, in the final DL shown in FIG. 40, the address B is not inthe same track as the alternation original area while, in the final DLshown in FIG. 41, the address B is in the same track as the alternationoriginal area.

In applications, an alternation replacement area existing in the sametrack or in a different track as the alternation original area have bothmerits and demerits. It needs to be chosen to use depending on theapplication. If the data generates a constraint imposed on the time toreproduce information of a file recorded on the recording medium 81, forexample, an alternation replacement area in the same track as thealternation original area is desirable. An example of such a data ismoving-picture data or audio data. If there is no constraint imposed onthe time to reproduce information of a database or the like recorded onthe recording medium 81 but there is a requirement of easy management ofdata, on the other hand, an alternation replacement area in a trackdifferent from that of the alternation original area offers merits.

As described above, an alternation replacement area existing in the sametrack as the alternation original area has a contradiction in that thelogical addresses are not continuous but the physical addresses arecontinuous. On the other hand, an alternation replacement area existingin a track different from that of the alternation original area shows acontradiction in that the logical addresses are continuous but thephysical addresses are not continuous. If data is recorded in such a waythat the contradictions are eliminated, however, the file to be recordedcan have any data format.

If an overwriting file is recorded on a new area without executingmanagement of alternation information at all, for example, the logicallayout will match the physical layout.

FIG. 42 shows a flowchart representing processing to actually recordoverwriting files sequentially into a new area without executingmanagement of alternation information at all.

The flowchart begins with a step S261 at which the file-systeminformation generation section 62 produces a result of determination asto whether or not a command to overwrite a new file on an alreadyexisting one or update an already existing file has been received. Thisprocess is carried out repeatedly till such a command is received. As acommand to overwrite a new file on an already existing one or update analready existing file is received, the flow of the processing goes on toa step S262 at which the file-system information generation section 62overwrites the new file into a new area or record the updated file in anew area.

To put it concretely, let us assume that, as shown in the upper portionof FIG. 43, an original file A has been recorded in an area from anaddress A to an address (A+3), and the file A is to be overwritten orupdated by a new file A′. In this case, as shown in the middle leftportion of FIG. 43, the file A′ is recorded as an overwriting orupdating file in an area ranging from an address B to an address (B+4)as a continuation area of the area used for recording the file A. Thus,as shown in the lower portion of FIG. 43, an area R1 representing alogical layout coincides with an area R2 representing a physical layout,causing no contradiction. As a result, for a file of any format,management of information and reproduction of data can be carried outwith ease. In addition, data can be read out from the recording medium81 at a high speed. It is to be noted that, in this case, the logicaladdress and the physical address of the overwriting or updating file areupdated or overwritten. Thus, as shown in the middle right portion, itis not necessary to catalog information such as the alternation originallocation, the alternation replacement location and the range on a DL.

By referring to a flowchart shown in FIG. 44, the following descriptionexplains processing, which is carried out to actually record data ontothe recording medium 81 when the recording medium 81 is mounted on therecording/reproduction apparatus. The processing, which is carried outto actually record data onto the recording medium 81 when the recordingmedium 81 is mounted on the recording/reproduction apparatus, isprocessing carried out for a case in which a DL has been recorded on therecording medium 81 in the temporary-DL format and read out from therecording medium 81 at a disc-mounting stage to examine the state of anarea represented by alternation replacement addresses and, if thealternation replacement addresses do not represent a contiguous area,noncontiguous areas represented by the alternation replacement addressesare converted into a single contiguous area. The temporary-DL format isa format in which information such as alternation replacement addressesis cataloged on the DL at an information granularity corresponding to acluster as it is. It is to be noted that processes carried out at stepsS262 to S269 of the flowchart shown in FIG. 44 are identical with theprocesses carried out at respectively the steps S222 and S225 to S231 ofthe flowchart shown in FIG. 39. It is thus unnecessary to repeat theexplanations of the processes.

Namely, at a step S261, the process described above is carried outrepeatedly until the recording medium 81 is mounted on therecording/reproduction apparatus. As the recording medium 81 is mountedon the recording/reproduction apparatus, the flow of the processing goeson to the step S262 to carry out a process of this step beforeperforming subsequent processes up to the step S269.

For example, as shown in the left and right upper portions of FIG. 45,on the upper temporary DL, a range of a cluster starting at a locationpointed to by an address A is associated with a range of a clusterstarting at a location pointed to by an address B. By the same token, arange of a cluster starting at a location pointed to by an address (A+1)is associated with a range of a cluster starting at a location pointedto by an address (B+1). In the same way, a range of a cluster startingat a location pointed to by an address (A+2) is associated with a rangeof a cluster starting at a location pointed to by an address (B+2).Likewise, a range of a cluster starting at a location pointed to by anaddress (A+3) is associated with a range of a cluster starting at alocation pointed to by an address (B+3). Therefore, the information isstored on the temporary DL at an information granularity correspondingto a cluster in a list format. Thus, the larger the number of clusters,the longer the DL.

By carrying out the processing to actually record data onto therecording medium 81 when the recording medium 81 is mounted on therecording/reproduction apparatus as explained earlier by referring tothe flowchart shown in FIG. 44, however, a final DL shown in the lowerportion of FIG. 45 shows that a range of four clusters starting at alocation pointed to by an address A is associated with a range of fourclusters starting at a location pointed to by an address B. To be morespecific, the list includes only a piece of information showing a pairof an alteration original range and an alteration replacement range aswell as the number of clusters in the range. Thus, the amount ofinformation stored on the DL can be reduced. As a result, by carryingout the processing shown in FIG. 44, a recording/reproduction apparatushaving no function to reconstruct a temporary DL into a final DL with asmaller size as described before by referring to the flowchart shown inFIG. 39 is capable of reducing the size of a temporary DL at the timethe recording medium 81 containing information recorded thereon ismounted on the recording/reproduction apparatus. Thus, the amount of anarea used for storing the final DL obtained as a result of subsequentprocessing can also be reduced.

In accordance with the present invention, in a process to incrementallyrecord information in an already existing file or update an alreadyexisting file, a user area or an SA area is used as alternate clusters.It is thus easy to update data and read out post-updating data for acase in which file-system information, anchor information, informationon the structure of the volume and database files of stream data must berecorded at fixed locations in the logical-address space. In addition,in the process to record the file-system information, the anchorinformation, the information on the structure of the volume and thedatabase files of stream data, only one of the file-system information,the anchor information, the information on the structure of the volumeand the database files of stream data can be selected as information tobe recorded in an SA area. Thus, the size of a used SA area can bereduced. Moreover, even for a case in which a file is updatedfrequently, it is no longer necessary to relocate the updated file in acontiguous recording area. It is thus possible to reduce the size of arecording area required in a process to incrementally record informationin a file already existing on a disk such as a write-once recordingmedium or update a file already existing on such a recording medium.Furthermore, information of an overwritten or updated file can berecorded in both a user area and an SA area, which each serve as analternate area for pre-overwriting and pre-updating information. Thus,the size of the used SA area can be reduced. In addition, in a processto record data, the layout of clusters cataloged on a temporary DL isconverted into a contiguous layout to decrease the size of a final DL,which is recorded on the recording medium 81 eventually.

Next, by referring to a flowchart shown in FIG. 46, the followingdescription explains the process carried out at the step S1 of theflowchart shown in FIG. 14 to set an SA area.

The flowchart shown in FIG. 46 begins with a step S291 at which theinitialization section 62 a of the file-system information generationsection 62 employed in the control section 51 controls the write section73 in order to drive the recording/reproduction block 53 to allocate anSA (Spare Area) area on the recording medium 81.

Then, in a process carried out at the next step S292, the initializationsection 62 a produces a result of determination as to whether or not anoverwriting process in a logical-address space has been set in use ofthe recording medium 81. An overwriting process in a logical-addressspace can be set by the user in advance so that the result ofdetermination can be produced on the basis of the setting made by theuser. As an alternative, at a stage prior to the start of a formattingprocess or right before the process of the step S292 is started, aselect screen is displayed as a screen for inquiring of the user inregard to whether or not the function of the overwriting process in alogical-address space is to be made effective. On the basis of aselection made by the user, the initialization section 62 a produces aresult of determination as to whether or not an overwriting process in alogical-address space has been set. As another alternative, anoverwriting process in a logical-address space is set by specifying anoption of a command.

If the determination result produced in the process carried out at thestep S292 indicates that an overwriting process in a logical-addressspace has been set, the flow of the processing goes on to a step S293 atwhich the initialization section 62 a sets a first portion of the SA(Spare Area) area as a TDMA area.

If the determination result produced in the process carried out at thestep S292 indicates that no overwriting process in a logical-addressspace has been set, on the other hand, the flow of the processing goeson to a step S294 at which the initialization section 62 a sets a secondportion smaller than the first portion of the SA (Spare Area) area as aTDMA area.

To be more specific, when the function of the overwriting process in alogical-address space is used, it is expected that physical informationrecorded on the recording medium 81 is updated frequently. Examples ofthe physical information are track management data and alternationinformation. Since physical information is updated frequently, it isalso expected that the size of the used TDMA increases. Thus, when thefunction of the overwriting process in a logical-address space is used,for example, as shown in the upper diagram of FIG. 47, a first portionwith a size of 50% in the SA area is set as a TDMA area. When thefunction of the overwriting process in a logical-address space is notused, on the other hand, a second portion with a size of 25% smallerthan the first portion in the SA area is set as a TDMA area for exampleas shown in the lower diagram of FIG. 47.

To put it concretely, in the upper diagram of FIG. 47, the first portionwith a size of 50% of the entire ISA is set as a TDMA represented by aportion L1 in the ISA. By the same token, the first portion with a sizeof 50% of the entire OSA is set as a TDMA represented by a portion L1′in the OSA. As shown in the lower diagram of FIG. 47, on the other hand,the second portion with a size of 25% of the entire ISA is set as a TDMArepresented by a portion L2 in the ISA. By the same token, the secondportion with a size of 25% of the entire OSA is set as a TDMArepresented by a portion L2′ in the OSA.

Thus, in the case of an ISA with a size of 256 MB, for example, when thefunction of the overwriting process in a logical-address space is used,a first portion with a size of 128 MB in the ISA area is set as a TDMAarea. When the function of the overwriting process in a logical-addressspace is not used, on the other hand, a first portion with a size of 64MB in the ISA area is set as a TDMA area.

In the case of an OSA with a size of 512 MB, for example, when thefunction of the overwriting process in a logical-address space is used,a first portion with a size of 256 MB in the OSA area is set as a TDMAarea. When the function of the overwriting process in a logical-addressspace is not used, on the other hand, a first portion with a size of 128MB in the OSA area is set as a TDMA area.

By carrying out the processing described above, it is possible to set aTDMA area with a size determined by whether or not the function of theoverwriting process in a logical-address space is used. Thus, when therecording medium 81 is utilized by using the function of the overwritingprocess in a logical-address space, it is possible to carry outprocessing to update physical information repeatedly.

By the way, when the FS is updated repeatedly due to execution of theprocessing described above, an SRR set as an area used for recordingFSes may conceivably become full. In such a case, a portion of free areais set as an area used for recording FSes. In this way, a new area to beused for recording FSes can be allocated. Processing to set a portion ofa free area as an area used for recording FSes will be described later.If FSes are recorded in separated areas in this way, however, it isfeared that a plurality of files will be read out at a lower speed. Inaddition, as the amount of alternation management information managed byusing a TDMA exceeds a predetermined value, the TDMA area is much usedin every updating process. Thus, it is feared that the TDMA area hasbeen all consumed in a few updating processes. In order to solve theseproblems, it is nice to provide a configuration in which the layout ofFSes is optimized to allow read and write operations to be carried outat a high speed.

FIG. 48 is a diagram showing the configuration of arecording/reproduction apparatus 22 allowing processing to optimize anarea used for recording FSes to be carried out.

It is to be noted that every component included in therecording/reproduction mechanism section 22 shown in FIG. 48 as acomponent identical with its counterpart employed in therecording/reproduction mechanism section 22 shown in FIG. 3 is denotedby the same reference numeral as the counterpart and the explanation ofthe component is properly omitted.

The configuration of the recording/reproduction mechanism section 22shown in FIG. 48 is different from the configuration of therecording/reproduction mechanism section 22 shown in FIG. 3 in that therecording/reproduction mechanism section 22 shown in FIG. 48 employs acontrol section 421 as a substitute for the control section 51 employedin the recording/reproduction mechanism section 22 shown in FIG. 3. Thecontrol section 421 is different from the control section 51 in that thecontrol section 431 further employs an optimization section 431 forexecuting a new function in addition to the function of the controlsection 51.

The optimization section 431 is a unit, which is used for optimizingFSes logically as well as physically when the size of a used TDMA areain the SA area on the recording medium 81 exceeds a predetermined value.

An FS-layer optimization section 431 a employed in the optimizationsection 431 is a unit for carrying out processing to optimize a logicalarea on an FS layer of information recorded on the recording medium 81.On the other hand, a physical-layer optimization section 431 b alsoemployed in the optimization section 431 is a unit for carrying outprocessing to optimize a physical layer of information recorded on therecording medium 81.

A division section 431 c, which is used for splitting a free SRR on therecording medium 81 into an area to be used for recording a new FS andan area to be used for recording a file when a recordable area of an SRRallocated to FSes is has been all consumed. This processing to split afree SRR (described in detail below) is carried out with a timing otherthan that of the optimization processing.

Next, the optimization processing is explained by referring to aflowchart shown in FIG. 49.

The flowchart begins with a step S311 at which the optimization section431 controls the read section 91 to read out the size of an all consumedarea of the TDMA in an SA area on the recording medium 81 and the sizeof a free area of an SRR allocated to FSes.

Then, at the next step S312, the optimization section 431 determineswhether or not the size of an all consumed area of the TDMA is at leastequal to a predetermined value. For example, if the amount of the mostrecent TDMA alternation management information is smaller than thepredetermined value, the flow of the processing goes back to the stepS311. That is, the processes of the steps S311 and S312 are carried outrepeatedly till the size of an all consumed area in the TDMA or theamount of the most recent TDMA alternation management information hasbecome at least equal to the predetermined value.

If the step S312 indicates that the size of an all consumed area in theTDMA has become at least equal to a predetermined value, the flow of theprocessing goes on to a step S313 at which the FS-layer optimizationsection 431 a reads out a plurality of FSes on the FS layer.

To be more specific, for example, an FS and file information referred toas Files in FIG. 50 have been logically recorded in blocks B301 and B302respectively as shown in the upper diagram of the figure. Also in thisstate, as shown in the lower diagram of FIG. 50, new file information isrecorded in a block B303 and the updating portion of the fileinformation recorded in the block B302 is recorded in a block B302′serving as an alternate area for the block B302. If an SRR allocated toFSes is filled up with the block B301 used for storing an FS and a blockB301′ used as an alternate area for storing replacement information ofthe FS stored in the block B301, a free area of an SRR including theblock B302 is split in division processing to be described later togenerate a first SRR to serve as a new FS area and a second SRR to serveas an area used for recording files. An FS is then recorded in a blockB301″ in the first SRR and an additional file is recorded in a blockB304 in the second SRR. The additional file is a stream file referred toas additional files (Stream) in the figure. It is to be noted thatnotation NWA shown in the figure denotes the beginning of an NWA (NewWritable Area) in the first or second SRRs. A new FS or a new file isrecorded in the new writable area in the SRR allocated to FSes or filesrespectively.

In the case of the example shown in the lower diagram of FIG. 50, forexample, the FS-layer optimization section 431 a reads out a pluralityof FSes recorded in blocks B301 and B301″, which are separated from eachother as shown in the upper diagram of FIG. 51 or the lower diagram ofFIG. 50. A black box shown in the figures represents a block in which anFS or a file has been recorded. On the other hand, a box hatched withslanting lines in the figures represents an alternate area.

At a step S314, the FS-layer optimization section 431 a collects theFSes read out from the blocks B301 and B301″, which are separated fromeach other, to synthesize the FSes into a single FS to be recorded in ablock 301″′ as shown in the lower diagram of FIG. 51.

To be more specific, in a process to read out a stream file, it isnecessary to read out the stream file after FSes read out initially. Itis thus feared that the time to read out a stream file is long. As shownin the upper diagram of FIG. 51, the FSes read out initially are theFSes recorded in the blocks B301 and B301″, which are separated fromeach other. By carrying out the processing described above, however,FSes are recorded on the FS layer logically as a single FS in order tooptimize the FS layer. Thus, the FSes can be read out only once. As aresult, the read and write speeds can be increased.

Then, at the next step S315, the physical-layer optimization section 431b reads out the FSes recorded on the recording medium 81 in a state ofbeing physically dispersed from each other.

That is, as shown in the upper diagram of FIG. 52, an FS and fileinformation referred to as Files in FIG. 52 have been logically recordedin blocks B321 and B322 respectively. Also, in this state, as shown inthe lower diagram of FIG. 52, new file information is recorded in ablock B323 and the updating portion of the file information recorded inthe block B322 is recorded in a block B332 serving as an alternate areafor the block B322. Accompanying this processing to record the new fileinformation, the FS recorded in a block B321 is updated. To put it indetail, information in a block B321′ within the block B321 is replacedwith information recorded in an alternate block B331′ of the ISA. On theother hand, information in a block B321″ within the block B321 isreplaced with information recorded also in the alternate block B331′.

At the step S315, the physical-layer optimization section 431 b readsout all FSes recorded in the blocks B321, B331′ and B331″ in a state ofbeing physically dispersed from each other for a case shown in the upperdiagram of FIG. 53 or the lower diagram of FIG. 52.

Then, at the next step S316, the physical-layer optimization section 431b collects the FSes recorded in a state of being physically dispersedfrom each other to synthesize the FSes into a single recorded FS.

To be more specific, the physical-layer optimization section 431 bcollects the FSes recorded in the blocks B321, B331′ and B331″ in astate of being physically dispersed from each other as shown in theupper diagram of FIG. 53 to synthesize the FSes into a single FS to berecorded into a block B341 as shown in the middle diagram of FIG. 53. Asa result, since the FSes are physically synthesized and recorded as asingle FS, the speed to read out the file can be raised.

At the next step S317, the physical-layer optimization section 431 bverifies that the operation to read out all FSes recorded in blocks in astate of being physically dispersed from each other, collects the FSes,synthesizes the FSes into a single FS and records the single FS into ablock. Subsequently, the physical-layer optimization section 431 brequests the optimization section 431 to issue an updateblock command tothe alternation-information generation section 64.

At the next step S318, the alternation-information generation section 64updates replacement information X into new replacement information X′ onthe basis of the updateblock command, and records the new replacementinformation X′ in a TDMA area. To be more specific, since the area usedfor recording the single FS is a physically contiguous area, almost allinformation to be managed by using the DL virtually no longer exists.Thus, the amount of replacement information decreases. To be morespecific, the replacement information X′ shown in the lower diagram ofFIG. 53 becomes a file with a size smaller than the replacementinformation X shown in the middle diagram of the same figure. Thus, evenif an already existing file is updated, a new file is added or anotherfile operation is carried out in the subsequent processing, the amountof replacement information to be updated in a TDMA area can be reduced.Therefore, the amount of the consumed TDMA area can also be decreased aswell.

By carrying out the optimization processing described above, areas usedfor recording FSes on the FS and physical layers can be collected into asingle area. Thus, the number of times an access to the TDMA is made canbe reduced so that the speeds to read out and write file information canbe increased. In addition, by reducing the amount of replacementinformation, it is possible to decrease the amount of the TDMA area,which is consumed when an already existing file is updated or a new fileis added in subsequent processing.

As a result, the following processing can be carried out. As shown inthe upper diagram of FIG. 54, an initial FS is recorded in a block B381and, by further updating the FS, replacement information is recorded ina block B382. In this state, since the SRR used for recording theinitial FS is all has been all consumed, let us assume that a further FSis recorded in a block B386. In addition, file information is recordedin a block B383 and a block B384. After the file information has beenrecorded in the block B384, the file information recorded in the blockB383 is updated to result in replacement information recorded in a blockB385. Then, additional file information referred to as additional files(Stream) in the figure is recorded in a block B387. By carrying out theprocesses of the steps S313 and S314 in this state, the FSes recorded inblocks B381 and B386 on the FS layer as shown in the upper diagram ofFIG. 54 are collected and synthesized into a single FS to be recorded ina block B401 as shown in the middle diagram of the same figure.

Then, by carrying out the processes of the steps S315 to S318, as shownin the lower diagram of FIG. 54, the FSes are physically collected andsynthesized to form a single FS, and replacement information Y recordedin the TDMA is updated into replacement information Y, having a smalleramount as information to be recorded.

By carrying out the processing described above, the number of times thereplacement information recorded in the TDMA is read out is reduced.Thus, the number of times an access to the TDMA is made is alsodecreased as well. As a result, the speeds to read out file informationfrom the recording medium 81 and write file information onto therecording medium 81 is increased. In addition, by reducing the amount ofreplacement information, it is possible to decrease the amount of theTDMA area, which is consumed when an already existing file is updated ora new file is added in subsequent processing.

Next, the division processing mentioned before is explained by referringto a flowchart shown in FIG. 55.

At a step S331, the division section 431 c determines whether or not theSRR allocated to FSes no longer includes a free area, that is, whetheror not the SRR is full. The process of this step is carried outrepeatedly till the SRR allocated to FSes no longer includes a freearea.

As shown in the upper diagram of FIG. 56, for example, an FS has beenrecorded in a block B501 whereas file information referred to as Filesin the figure has been recorded in a block B502 and, in this state, newfile information is added to a block B503 or the file informationrecorded in the block B502 is updated to result in information recordedin an alternate block B502′. Accompanying this process, the FS recordedin the block B501 is updated to consume a block B501′ so that SRR #2allocated to FSes becomes full. In this case, at the step S331 indicatesthat the SRR allocated to FSes no longer includes a free area, causingthe flow of the processing to go on to a step S332.

At the step S332, the division section 431 c divides a free SRR into twopartial areas. Then, at the next step S333, an area to be allocated toFSes is set in one of the partial areas and an area to be allocated tofiles is set in the other partial areas. Subsequently, the flow of theprocessing goes back to the step S331.

To be more specific, in the case of the example shown in the middlediagram of FIG. 56, SRR #3 used for recording file information isdivided into SRR #4 set as an area allocated to FSes and SRR #5 set as atrack allocated to files, that is, a track to be used for recording fileinformation as shown in the lower diagram of FIG. 56.

There are some methods for dividing an SRR as described as follows.

In accordance with a first method, an SRR is divided by execution of acommand called Reserve (A, B). Typically, there is a reserve commandcalled Reserve (A) to be executed to reserve an area with a size A. Thecommand called Reserve (A, B) is an extension of the reserve commandcalled Reserve (A). The command called Reserve (A, B) is executed toreserve an area with a size A and another area with a size B.

In accordance with a second method, an SRR is divided by execution of acommand called Split (X, A). The command called Split (X, A) is executedto split a track X (SRR #X) into an area with a size A and a remainingarea. Thus, by execution of this command, a specified track is dividedinto two areas.

To be more specific, a recorded block B531 exists in an SRR (track #n)in an open state as shown in FIG. 57. The SRR (track #n) in an openstate is referred to as an Open Reserved Track (Track #n). The blockB531 corresponds for example to an area obtained as a result ofcombining blocks B502, B503 and B502′ as shown in the middle diagram ofFIG. 56.

In the case of the example shown in the upper diagram of FIG. 57, thecommand called Split (n, A) is executed to divide a track n referred toas Track #n into areas shown in the middle diagram of the figure. To putit concretely, the track #n is split into a block B532 with a size A anda remaining block B533. Composed of blocks B531 and B541, the block 532is a track n referred to as an Open Reserved Track (Track #n) in themiddle diagram of the figure. On the other hand, the block 533 is theremaining track (n+1) referred to as an Open Reserved Track (Track#(n+1)) in the middle diagram of the figure. If compared with the lowerdiagram of FIG. 56, the block B541 corresponds to the track allocated toFSes and the block B521 corresponds to the track allocated to files. Inthe example shown in the middle diagram of FIG. 57, however, the blocksB541 and B531 exist in the same track. Thus, further information is tobe recorded in the block B541 adjacently following the recorded blockB531.

In accordance with a third method, a command called Split (X, A, B) isexecuted as an extension command of the split command provided by thesecond method. The command called Split (X, A, B) is executed to split atrack X (SRR #X) into three areas, i.e., an area with a size A, an areawith a size B and a remaining area. Thus, by execution of this command,a specified track is divided into three areas.

In accordance with a fourth method, a command called Split′ (Y, A) isexecuted as an extension command of the split command provided by thesecond method. The command called Split′ (Y, A) is executed to split atrack Y (SRR #Y) into three areas, i.e., an already recorded area, anarea with a size A and a remaining area. Thus, by execution of thiscommand, a specified track is divided into three areas.

In the case of the example shown in the upper diagram of FIG. 57, Split′(n, A) is executed to divide a track n referred to as Track #n intoareas shown in the lower diagram of the figure. To put it concretely,the track #n is split into a block B531, a block B551 with a size A anda remaining block B552. The block 531 is an already recorded track nreferred to as a Closed Reserved Track (Track #n) in the lower diagramof the figure. The block 551 is a track (n+1) referred to as an OpenReserved Track (Track #(n+1)) in the middle diagram of the figure. Theblock 552 is the remaining track (n+2) referred to as an Open ReservedTrack (Track #(n+2)) in the middle diagram of the figure. If comparedwith the lower diagram of FIG. 56, the block B551 corresponds to thetrack allocated to FSes and the block B552 corresponds to the trackallocated to files.

As shown in the middle diagram of FIG. 56, however, while the Splitcommand divides an open original track into open tracks (SRRs), theSplit′ command results in an already recorded area in a closed state.

In accordance with a fifth method, a command called Split′ (Y, A, B) isexecuted as an extension command of Split′ (Y, A) provided by the fourthmethod. The command called Split′ (Y, A, B) is executed to split a trackY (SRR #Y) into 4 areas, i.e., an already recorded area, an area with asize A, an area with a size B and a remaining area. Thus, by executionof this command, a specified track is divided into four areas.

In the commands described above, notations A and B each denote aparameter specifying the size of an area obtained as a result ofexecution of the command. However, the parameters A and B may also eachspecify a position at which splitting is started. In addition, in thecase of the Split′ command, by using fewer parameters than those of theSplit command, more areas obtained as a result of the splitting can beobtained. As a result, the number of bits composing parameters of thecommand can be reduced to a required minimum but the parameters can yetbe utilized effectively. As is obvious from the above descriptions, anSRR can be divided into a maximum of four areas. By adopting the sametechnique as the commands described above, however, another command canbe used to divide an SRR into more than four areas.

By carrying out the processing described above, a new SRR allocated toFSes can be set as an existing SRR is filled up with FSes.

As described above, an area is set as an area used for recording a mainFS. It is to be noted, however, that the same technique can be appliedto a case in which an area is set as an area used for recording a mirrorFS.

Next, processing to divide an area into portions used for setting amirror FS is explained by referring to a flowchart shown in FIG. 58.

At a step S351, the division section 431 c produces a result ofdetermination as to whether or not the SRR allocated to mirror FSes nolonger includes a free area, that is, whether or not the SRR is full.The process of this step is carried out repeatedly till the SRRallocated to mirror FSes no longer includes a free area.

As shown in the upper diagram of FIG. 59, for example, a main FS hasbeen recorded in a block B571, a mirror FS has been recorded in a blockB573 and file information referred to as Files in the figure has beenrecorded in a block B572 and, in this state, additional file informationis recorded in a block B581, the main FS recorded in the block B571 isupdated into a new main FS recorded in a block B571′ and the mirror FSrecorded in the block B573 is updated into a new mirror FS recorded in ablock B573′ as shown in the middle diagram of the figure. As a result,SRR #4 allocated to mirror FSes becomes full. In this case, thedetermination result produced in the process carried out at the stepS351 indicates that the SRR allocated to mirror FSes no longer includesa free area, then goes on to a step S352.

At the step S352, the division section 431 c divides a free SRR into twopartial areas. Then, at the next step S353, an area to be allocated toFSes is set in one of the partial areas and an area to be allocated tofiles is set in the other partial areas. Subsequently, the flow of theprocessing goes back to the step S351.

To be more specific, in the case of the example shown in the middlediagram of FIG. 59, SRR #3 used for recording file information isdivided into SRR #4 set as an area allocated to mirror FSes and SRR #5set as a track allocated to files, that is, a track to be used forrecording file information as shown in the lower diagram of FIG. 59.

Methods to divide an SRR in this case are similar to the methodsdescribed above for a main FS except that it is nice to set an areaallocated to mirror FSes at a location close to an SRR allocated tomirror FSes.

In addition, if the size of an area dedicated for main FSes is equal tothe size of an area dedicated for mirror FSes, it is quite within thebounds of possibility that both the area dedicated for main FSes and thearea dedicated for mirror FSes are filled up at the same time. In such acase, one of the above commands can be executed to divide a free areainto four tracks or four areas, i.e., an already recorded area, an areaallocated to files, an area allocated to main FSes and an area allocatedto mirror FSes. In addition, if the resulting area allocated to mirrorFSes is at a location close to the original area allocated to main FSes,the reading and writing speeds can be prevented from decreasing.

By carrying out the processing described above, a new SRR allocated tomirror FSes can be set as an existing SRR is filled up with mirror FSes.

The series of processes described previously can be carried out byhardware and/or execution of software. If the series of processesdescribed above is carried out by execution of software, programscomposing the software can be installed into a computer embedded indedicated hardware, a general-purpose personal computer or the like fromtypically a recording medium. In this case, the computer or the personalcomputer serves as the recording/reproduction apparatus described above.By installing a variety of programs into the general-purpose personalcomputer, the personal computer is capable of carrying out a variety offunctions.

The aforementioned recording medium for recording programs to beinstalled into a computer or a general-purpose personal computer asprograms to be executed by the computer or the general-purpose personalcomputer respectively is a removable recording medium provided to theuser separately from the main unit of the recording/reproductionapparatus as shown in FIG. 2. Examples of the removable recordingmediums also each referred to as a package medium include the magneticdisk 41 such as a flexible disk, the optical disk 42 such as a CD-ROM(Compact Disk-Read Only Memory) or a DVD (Digital Versatile Disk), themagneto-optical disk 43 such as an MD (Mini Disk) as well as thesemiconductor memory 44. Instead of installing the programs from theremovable recording mediums, the programs can also be stored in advancein an embedded recording medium included in the main unit of thecomputer or the general-purpose personal computer. Examples of theembedded recording medium are a hard disk included in the storagesection 18 and the ROM 12.

It is also worth noting that, in this specification, steps of a programrecorded on the recording medium as a program implementing a flowchartdescribed above can be carried out not only in a pre-prescribed orderalong the time axis, but also concurrently or individually.

In addition, it should be understood by those skilled in the art that avariety of modifications, combinations, sub-combinations and alterationsmay occur in dependence on design requirements and other factors insofaras they are within the scope of the appended claims or the equivalentsthereof.

1. An information-recording apparatus comprising: arecording/reproducing unit configured to read data from a computerreadable recording medium and to record data to the computer readablerecording medium; and track division means for dividing, in response toa command, a track previously allocated on said computer readablerecording medium for storing files into a first area and a second areawhen a track on the computer readable storage medium allocated to filesystems no longer has a free area, and allocating the first area as atrack for storing file systems and the second area as a track forstoring files other than the file systems.
 2. The information-recordingapparatus according to claim 1, wherein said command has a parameter forspecifying an original track to be divided and one or more parametersfor specifying sizes or locations of resulting areas obtained as aresult of division of said original track; and said track division meansdivides said original track into said resulting areas, which start fromthe beginning of said original track and are defined by said sizes orsaid locations, and a remaining area, setting free portions of saidresulting areas and said remaining area as a track allocated to filessystems and a track allocated to files.
 3. The information-recordingapparatus according to claim 1, wherein said command has a parameter forspecifying an original track to be divided and one or more parametersfor specifying sizes or locations of resulting areas obtained as aresult of division of said original track; and said track division meansdivides said original track into an already recorded area starting fromthe beginning of said original track, free areas, which follow saidalready recorded area and are defined by said sizes or said locations,and a remaining area, setting said free areas and said remaining area asa track allocated to file systems and a track allocated to files.
 4. Theinformation-recording apparatus according to claim 1, wherein when atrack set on a recording medium as a track allocated to main filesystems or mirror file systems no longer has a free area, on the basisof a command, said track division means divides a track previouslyallocated on said recording medium to files into an area to be used as atrack allocated to main file systems or mirror file systems and an areato be used as a track allocated to files.
 5. An information-recordingmethod comprising: dividing, with a processor in response to a command,a track previously allocated on a computer readable recording medium forstoring files into a first area and a second area when a track on thecomputer readable storage medium allocated to file systems no longer hasa free area; and allocating, with the processor, the first area as atrack for storing file systems and the second area as a track forstoring files other than the file systems.
 6. A tangible computerreadable storage medium encoded with instructions which when executed bya computer, causes the computer to implement a method comprising:dividing, in response to a command, a track previously allocated on acomputer readable recording medium for storing files into a first areaand a second area when a track on the computer readable storage mediumallocated to file systems no longer has a free area; and allocating thefirst area as a track for storing file systems and the second area as atrack for storing files other than the file systems.
 7. Aninformation-recording apparatus comprising: a recording/reproducing unitconfigured to read data from a computer readable recording medium and torecord data to the computer readable recording medium; and a trackdivision unit configured to divide, in response to a command, a trackpreviously allocated on said computer readable recording medium forstoring files into a first area and a second area when a track on thecomputer readable storage medium allocated to file systems no longer hasa free area, and to allocate the first area as a track for storing filesystems and the second area as a track for storing files other than thefile systems.